Equilibrium of vegetation and climate at the European rear edge. A reference for climate change planning in mountainous Mediterranean regions.

PubMed

Ruiz-Labourdette, Diego; Martínez, Felipe; Martín-López, Berta; Montes, Carlos; Pineda, Francisco D

2011-05-01

Mediterranean mountains harbour some of Europe's highest floristic richness. This is accounted for largely by the mesoclimatic variety in these areas, along with the co-occurrence of a small area of Eurosiberian, Boreal and Mediterranean species, and those of Tertiary Subtropical origin. Throughout the twenty-first century, we are likely to witness a climate change-related modification of the biogeographic scenario in these mountains, and there is therefore a need for accurate climate regionalisations to serve as a reference of the abundance and distribution of species and communities, particularly those of a relictic nature. This paper presents an objective mapping method focussing on climate regions in a mountain range. The procedure was tested in the Cordillera Central Mountains of the Iberian Peninsula, in the western Mediterranean, one of the ranges occupying the largest area of the Mediterranean Basin. This regionalisation is based upon multivariate analyses and upon detailed cartography employing 27 climatic variables. We used spatial interpolation of data based on geographic information. We detected high climatic diversity in the mountain range studied. We identified 13 climatic regions, all of which form a varying mosaic throughout the annual temperature and rainfall cycle. This heterogeneity results from two geographically opposed gradients. The first one is the Mediterranean-Euro-Siberian variation of the mountain range. The second gradient involves the degree of oceanicity, which is negatively related to distance from the Atlantic Ocean. The existing correlation between the climatic regions detected and the flora existing therein enables the results to be situated within the projected trends of global warming, and their biogeographic and ecological consequences to be analysed.

Climate change velocity underestimates climate change exposure in mountainous regions

PubMed Central

Dobrowski, Solomon Z.; Parks, Sean A.

2016-01-01

Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported. PMID:27476545

Mountains as early warning indicators of climate change

NASA Astrophysics Data System (ADS)

Williams, M. W.

2015-12-01

The panoramic splendor and complexity of mountain environments have inspired and challenged humans for centuries. These areas have been variously perceived as physical structures to be conquered, as sites of spiritual inspiration, and as some of the last untamed natural places on Earth. In our time, the perception that "mountains are forever" may provide solace to those seeking stability in a rapidly changing world. However, changes in the hydrology and in the abundance and species composition of the native flora and fauna of mountain ecosystems are potential bellwethers of global change, because these systems have a propensity to amplify environmental changes within specific portions of this landscape. Mountain areas are thus sentinels of climate change. We are seeing effects today in case histories I present from the Himalaya's, Andes, Alps, and Rocky Mountains. Furthermore, these ecosystem changes are occurring in mountain areas before they occur in downstream ecosystems. Thus, mountains are early warning indicators of perturbations such as climate change. The sensitivity of mountain ecosystems begs for enhanced protection and worldwide protection. Our understanding of the processes that control mountain ecosystems—climate interactions, snowmelt runoff, biotic diversity, nutrient cycling—is much less developed compared to downstream ecosystems where human habitation and development has resulted in large investments in scientific knowledge to sustain health and agriculture. To address these deficiencies, I propose the formation of an international mountain research consortium.

A comparative review of multi-risk modelling methodologies for climate change adaptation in mountain regions

NASA Astrophysics Data System (ADS)

Terzi, Stefano; Torresan, Silvia; Schneiderbauer, Stefan

2017-04-01

Keywords: Climate change, mountain regions, multi-risk assessment, climate change adaptation. Climate change has already led to a wide range of impacts on the environment, the economy and society. Adaptation actions are needed to cope with the impacts that have already occurred (e.g. storms, glaciers melting, floods, droughts) and to prepare for future scenarios of climate change. Mountain environment is particularly vulnerable to the climate changes due to its exposure to recent climate warming (e.g. water regime changes, thawing of permafrost) and due to the high degree of specialization of both natural and human systems (e.g. alpine species, valley population density, tourism-based economy). As a consequence, the mountain local governments are encouraged to undertake territorial governance policies to climate change, considering multi-risks and opportunities for the mountain economy and identifying the best portfolio of adaptation strategies. This study aims to provide a literature review of available qualitative and quantitative tools, methodological guidelines and best practices to conduct multi-risk assessments in the mountain environment within the context of climate change. We analyzed multi-risk modelling and assessment methods applied in alpine regions (e.g. event trees, Bayesian Networks, Agent Based Models) in order to identify key concepts (exposure, resilience, vulnerability, risk, adaptive capacity), climatic drivers, cause-effect relationships and socio-ecological systems to be integrated in a comprehensive framework. The main outcomes of the review, including a comparison of existing techniques based on different criteria (e.g. scale of analysis, targeted questions, level of complexity) and a snapshot of the developed multi-risk framework for climate change adaptation will be here presented and discussed.

Connecting Current Research on Climate and Snow with Individuals Who Care

NASA Astrophysics Data System (ADS)

Moore, C. E.; Denning, S.

2015-12-01

A growing body of research explores the effects of climate change on snow in the Southern Rocky Mountains. This research includes observing climate and weather patterns, modeling potential future winter climate and snowpack, and exploring how these changes will affect the ecosystems, people, and industries that rely on frozen reservoirs of seasonal snow. We review existing resources for non-scientists on this topic, and explain how climate and snow are changing in the Southern Rocky Mountains. The Southern Rockies urban corridor is home to a growing population of people who rely directly on snowmelt runoff for daily life, health, and prosperity. Many of these people also seek refuge from growing urbanization by escaping to the mountains. Meanwhile, high elevations in the Rockies are already experiencing noticeable effects of climate change. Individuals with personal connections to the mountains make a ready audience to receive accessible science communication grounded in current research. People who care about mountains may be inspired to join the conversation and take action in their own lives as they learn what is already changing and what they might expect to find in winters to come.

Western Mountain Initiative - Research Links

Science.gov Websites

Parks programS Forest Service Climate Change Resource Center (CCRC) North American Nitrogen Center to be told." US Global Change Research Program (GlobalChange.gov) USGS Climate and Land Use Rocky Mountain Science Center Global Change Research Program -- A Focus on Mountain Ecosystems Western

Mountains, Climate Change and North American Water Security

NASA Astrophysics Data System (ADS)

Pomeroy, J. W.; Fang, X.; Whitfield, P. H.; Rasouli, K.; Harder, P.; Siemens, E.; Pradhananga, D.

2016-12-01

The juxtaposition of cold high precipitation catchments in mountains and low precipitation in downstream lowlands means that mountain water supplies support over half the world's population and sustain most irrigation agriculture. How secure is this mountain water in northern North America? Irrigation and other consumptive downstream uses have put immense pressure on water supplied from the Canadian Rockies. Excess water from these rivers also carries risk. Downstream communities are often located in the flood plains of mountain rivers, making them subject to the extreme hydrometeorology of the headwaters as was evident in the BC/Alberta/Saskatchewan floods of 2013 and droughts of 2015/2016. Climate change is disproportionately warming high mountain areas and the impacts of warming on water are magnified in high mountains because seasonal snowpacks, perennial snowfields and glaciers form important stores of water and control the timing of release of water and the seasonal and annual discharge of major mountain rivers. Changes in mountain snow and glacial regimes are rapidly occurring in Western Canada and this is already impacting downstream water security by changing flood risk, streamflow timing and volume. Hydrological process modelling is diagnosing the causes of intensification of hydrological cycling and coupled to climate models suggesting that the timing and quantity of mountain waters will shift under certain climate, glacier cover and forest cover scenarios and so impact the water security of downstream food production. So far, changes in precipitation are matched by evapotranspiration and sublimation providing some resilience to change in streamflow due to intensification of hydrological cycling. Faster glacier melt in drought periods has buffered low flows but this capacity id dwindling as glaciers ablate. The International Network for Alpine Research Catchment Hydrology (INARCH) project of GEWEX is quantifying water resiliency and risk in mountain headwaters so as to better assess the water security of downstream regions. INARCH results from Western Canada suggest current mountain river resiliency is at risk from increased climate variability as rainfall runoff replaces snowmelt and glacier melt runoff processes.

The Impact Snow Albedo Feedback over Mountain Regions as Examined through High-Resolution Regional Climate Change Experiments over the Rocky Mountains

NASA Astrophysics Data System (ADS)

Letcher, Theodore

As the climate warms, the snow albedo feedback (SAF) will play a substantial role in shaping the climate response of mid-latitude mountain regions with transient snow cover. One such region is the Rocky Mountains of the western United States where large snow packs accumulate during the winter and persist throughout the spring. In this dissertation, the Weather Research and Forecast model (WRF) configured as a regional climate model is used to investigate the role of the SAF in determining the regional climate response to forced anthropogenic climate change. The regional effects of climate change are investigated by using the pseudo global warming (PGW) framework, which is an experimental configuration in a which a mean climate perturbation is added to the boundary forcing of a regional model, thus preserving the large-scale circulation entering the region through the model boundaries and isolating the mesoscale climate response. Using this framework, the impact of the SAF on the regional energetics and atmospheric dynamics is examined and quantified. Linear feedback analysis is used to quantify the strength of the SAF over the Headwaters region of the Colorado Rockies for a series of high-resolution PGW experiments. This technique is used to test sensitivity of the feedback strength to model resolution and land surface model. Over the Colorado Rockies, and integrated over the entire spring season, the SAF strength is largely insensitive to model resolution, however there are more substantial differences on the sub-seasonal (monthly) timescale. In contrast, the SAF strength over this region is very sensitive to choice of land surface model. These simulations are also used to investigate how spatial and diurnal variability in warming caused by the SAF influences the dynamics of thermally driven mountain-breeze circulations. It is shown that, the SAF causes stronger daytime mountain-breeze circulations by increasing the warming on the mountains slopes thus enhancing the thermal contrast between the mountain slopes and the surrounding lowlands which drives these wind systems. This analysis is extended to investigate the impacts that the SAF has on the large-scale mountain-plain circulation that develops east of the Rockies over the Great Plains. To help isolate the SAF, a more idealized regional climate experiment which isolates the SAF is performed. It was found that SAF may influence thermally driven atmospheric dynamics up-to 200km east of the Mountains where the SAF originates, suggesting broader regional impacts of the SAF which may not be well resolved by coarser resolution global climate models. The implications of these changes on pollution transport and moist convection are also explored using these simulations.

The Hydrological Response of Snowmelt Dominated Catchments to Climate Change

NASA Astrophysics Data System (ADS)

Arrigoni, A. S.; Moore, J. N.

2007-12-01

Hydrological systems dominated by snowmelt discharge contribute greater than half the freshwater resource available to the western United States. Globally, the contribution of mountain discharge to total runoff is twice the expected for their geographical coverage. Therefore, snowmelt dominated mountain catchments have proportionally a more prominent role than other systems to our freshwater resource. A changing climate, or even a more variable climate, could have a significant impact on these systems, and consequently on our freshwater resource. Ergo, a better understanding of how changes and variations in climate will influence mountain catchments is a necessity for improving future water management under predicted/proposed climate change. The research presented here is a first order analysis to improve our understanding of these systems by monitoring and analyzing high mountain catchments along the entirety of the Mission Mountain Front, Montana USA. The Mission Mountain Range is an ideal location for conducting this research as it runs directly north to south with elevations progressively increasing from 7600 feet in the northern section, to over 9700 feet at the southern end. The lower elevation catchments will be used as surrogates for variable climate change, while the high elevation catchments will be used as surrogates for a more stable, cooler, climate regime. We use a combination of USGS and Tribal stream gauges, as well as stage gauge loggers in the headwaters of the catchments, SNOTEL datasets, and weather station datasets. This information is used to determine if, how, and why the snowmelt hydrographs vary between catchments, within the catchments between the upper and lower segments, and the dominant driver or drivers of the hydrograph form in relation to changing climatic variables such as temperature and precipitation. This research will improve current comprehension of how mountain catchments respond to climatic variables, and additionally will expand upon the current understanding of general catchment hydrology.

Mountain-climbing bears protect cherry species from global warming through vertical seed dispersal.

PubMed

Naoe, Shoji; Tayasu, Ichiro; Sakai, Yoichiro; Masaki, Takashi; Kobayashi, Kazuki; Nakajima, Akiko; Sato, Yoshikazu; Yamazaki, Koji; Kiyokawa, Hiroki; Koike, Shinsuke

2016-04-25

In a warming climate, temperature-sensitive plants must move toward colder areas, that is, higher latitude or altitude, by seed dispersal [1]. Considering that the temperature drop with increasing altitude (-0.65°C per 100 m altitude) is one hundred to a thousand times larger than that of the equivalent latitudinal distance [2], vertical seed dispersal is probably a key process for plant escape from warming temperatures. In fact, plant geographical distributions are tracking global warming altitudinally rather than latitudinally, and the extent of tracking is considered to be large in plants with better-dispersed traits (e.g., lighter seeds in wind-dispersed plants) [1]. However, no study has evaluated vertical seed dispersal itself due to technical difficulty or high cost. Here, we show using a stable oxygen isotope that black bears disperse seeds of wild cherry over several hundred meters vertically, and that the dispersal direction is heavily biased towards the mountain tops. Mountain climbing by bears following spring-to-summer plant phenology is likely the cause of this biased seed dispersal. These results suggest that spring- and summer-fruiting plants dispersed by animals may have high potential to escape global warming. Our results also indicate that the direction of vertical seed dispersal can be unexpectedly biased, and highlight the importance of considering seed dispersal direction to understand plant responses to past and future climate change. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fire history and climate characteristics during the last millennium of the Great Hinggan Mountains at the monsoon margin in northeastern China

NASA Astrophysics Data System (ADS)

Gao, Chuanyu; He, Jiabao; Zhang, Yan; Cong, Jinxin; Han, Dongxue; Wang, Guoping

2018-03-01

The northeastern region of China, at the limit of the summer monsoon, is characterized by the presence of mountains that influenced by the Asian summer monsoon on one side and the westerlies on the other; however, few studies have compared the environmental characteristics on the two sides of these mountains. In this study, two peatland cores from the western and eastern sides of the Great Hinggan Mountains were investigated to better understand the climatic and environmental conditions and the measurements of black carbon (BC) and δ13C-BC were used to reconstruct the fire history and environmental characteristics during the last millennium. Our results showed that the variations in the δ13C-BC values are more sensitive to climate changes than the BC fluxes, and the climate forcing mechanisms differed between the two sides of the mountains. Lower δ13C-BC values around 500 cal yr BP on the western side of the mountains indicated climate conditions were wetter than that on the eastern side, and were influenced by low sea surface temperatures in the North Atlantic Ocean. The region east of the mountains was mainly influenced by the strong Asian summer monsoon, and the decreasing of δ13C-BC values indicated climate conditions became wetter from 250 cal yr BP to the present and were wetter than that on the western side after 150 cal yr BP. Moreover, when one of these two forcing factors weakened and the other strengthened (e.g. from 400 to 150 cal yr BP), climate conditions in these two sides were similar.

Elevational shifts in thermal suitability for mountain pine beetle population growth in a changing climate

Treesearch

Barbara J. Bentz; Jacob P. Duncan; James A. Powell

2016-01-01

Future forests are being shaped by changing climate and disturbances. Climate change is causing large-scale forest declines globally, in addition to distributional shifts of many tree species. Because environmental cues dictate insect seasonality and population success, climate change is also influencing tree-killing bark beetles. The mountain pine beetle,...

Perspectives on climate change, mountain hydrology, and water resources in the Oregon Cascades, USA

Treesearch

A.W. Nolin

2012-01-01

From both social and environmental perspectives, water is the main connection between highland and lowland processes in mountain watersheds: Water flows downhill while human impacts flow uphill. For example, in the Oregon Cascades mountain range, geology, vegetation, and climate influence the hydrologic connections within watersheds. Geology determines which watersheds...

Great Basin paleoenvironmental studies project; Third quarterly technical progress report, December 1993--February 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1994-04-01

Examination of the paleolithic and geomorphic records to determine the local and regional impact of past climates will advance assessment of Yucca Mountain`s suitability as a high-level nuclear waste repository. The project includes the integration of botanical, faunal, and geomorphic components to accomplish this goal. Paleobotanical studies will reconstruct the response of vegetation to climate change at the community and the organismal levels by integrating data obtained from nearly continuous sediment records of pollen, plant macrofossils, and stable isotopes from fossil woodrat middens. The goal of the paleofaunas study is to construct a history of Great Basin vertebrates, particularly mammals,more » that will provide empirical evidence of past environmental and climatic conditions within the Great Basin as it is recorded by the animals. Taxonomic composition of archaeological and paleontological faunas from various areas within the Great Basin and morphological change within individual mammalian taxa at specific localities are being investigated to monitor faunal response to changing environmental conditions. The objective of the geomorphology component of the paleoenvironmental program is to document the responses of surficial processes and landforms to the climatic changes documented by studies of packrat middens, pollen, and faunal distributions. The project will focus on: (1) stratigraphic relationships between lake deposits and aeolian or fluvial sediments and landforms; (2) cut and fill sequences in floodplain and river-channel deposits; (3) identification of periods of dune mobility and stability; (4) documentation of episodes of alluvial fan and terrace development and erosion; and (5) correlation of (3) and (4) to climatically driven lake-level fluctuation as revealed by shoreline features such as strandlines and beach ridges. Accomplishments for this period are presented for these studies.« less

Influence of orographic precipitation on the incision within a mountain-piedmont system

NASA Astrophysics Data System (ADS)

Zavala, Valeria; Carretier, Sébastien; Bonnet, Stephane

2017-04-01

The geomorphological evolution of a mountain-piedmont system depends both on tectonics and climate, as well as on couplings between the mountain and its piedmont. Although the interactions between climate and tectonics are a fundamental point for understanding the landscape evolution, the erosion of a mountain range and the sediment deposition at the mountain front, or piedmont, have been poorly studied as a coupled system. Here we focus on the conditions driving an incision within such a system. Classically, it is thought that incision results from a change in climate or uplift rates. However, it is not clear which are the specific conditions that favor the occurrence of river incision in the piedmont. In particular, studies have shown that the presence of a piedmont can modify the incision patterns, and even drive autogenic incision, without any change in external forcings. This is a crucial issue in order to interpret natural incisions in terms of uplift or climatic modifications. Such a problem is further complicated by the modification of local precipitations and temperatures during uplift, because the progressive effect of climate change may superimpose to uplift. In this work we explore the hypothesis that a mountain-piedmont coupled system may develop incision in its piedmont as a result of enhanced orographic precipitations during surface uplift. We use a landscape evolution model, Cidre, in order to explore the response of a mountain-piemont system in which the mountain is continuously uplifted but in which precipitation rates depend on elevations. Thus precipitation amounts change during the mountain uplift. We test different peaks and amplitudes of the orographic precipitation pattern, maintaining the other conditions constant. Preliminary results show that elevation-dependent precipitations drive temporary but pronounced incisions of the main rivers within the piedmont, contrary to experiments without orographic precipitations.

The NextData Project: a national Italian system for the retrieval, storage, access and diffusion of environmental and climate data from mountain and marine areas

NASA Astrophysics Data System (ADS)

Provenzale, Antonello

2013-04-01

Mountains are sentinels of climate and environmental change and many marine regions provide information on past climate variations. The Project of Interest NextData will favour the implementation of measurement networks in remote mountain and marine areas and will develop efficient web portals to access meteoclimatic and atmospheric composition data, past climate information from ice and sediment cores, biodiversity and ecosystem data, measurements of the hydrological cycle, marine reanalyses and climate projections at global and regional scale. New data on the present and past climatic variability and future climate projections in the Alps, the Himalaya-Karakoram, the Mediterranean region and other areas of interest will be obtained and made available. The pilot studies conducted during the project will allow for obtaining new estimates on the availability of water resources and on the effects of atmospheric aerosols on high-altitude environments, as well as new assessments of the impact of climate change on ecosystems, health and societies in mountain regions. The system of archives and the scientific results produced by the NextData project will provide a unique data base for research, for environmental management and for the estimate of climate change impacts, allowing for the development of knowledge-based environmental and climate adaptation policies.

Spatial variability in forest growth—climate relationships in the Olympic Mountains, Washington.

Treesearch

Jill M. Nakawatase; David L. Peterson

2006-01-01

For many Pacific Northwest forests, little is known about the spatial and temporal variability in tree growth - climate relationships, yet it is this information that is needed to predict how forests will respond to future climatic change. We studied the effects of climatic variability on forest growth at 74 plots in the western and northeastern Olympic Mountains....

Mountain Plant Community Sentinels: AWOL

NASA Astrophysics Data System (ADS)

Malanson, G. P.

2017-12-01

Mountain plant communities are thought to be sensitive to climate change. Because climatic gradients are steep on mountain slopes, the spatial response of plant communities to climate change should be compressed and easier to detect. These expectations have led to identifying mountain plant communities as sentinels for climate change. This idea has, however, been criticized. Two critiques, for alpine treeline and alpine tundra, are rehearsed and supplemented. The critique of alpine treeline as sentinel is bolstered with new model results on the confounding role of dispersal mechanisms and sensitivity to climatic volatility. In alpine tundra, for which background turnover rates have yet to be established, community composition may reflect environmental gradients only for extremes where effects of climate are most indirect. Both plant communities, while primarily determined by energy at broad scales, may respond to water as a proximate driver at local scales. These plant communities may not be in equilibrium with climate, and differently scaled time lags may mean that ongoing vegetation change may not signal ongoing climate change (or lack thereof). In both cases a double-whammy is created by scale dependence for time lags and for drivers leading to confusion, but these cases present opportunities for insights into basic ecology.

Climate change, fish, and aquatic habitat in the Blue Mountains [Chapter 5

Treesearch

Daniel J. Isaak; Katherine Ramsey; John C. Chatel; Deborah L. Konnoff; Robert A. Gecy; Dona Horan

2017-01-01

National Forest System lands in the Blue Mountains region support a diversity of important native aquatic species that will be affected by climate change. As part of the Blue Mountains Adaptation Partnership, four of these species (spring Chinook salmon (Oncorhynchus tshawytscha Walbaum in Artedi), bull trout (Salvelinus confluentus Suckley), summer steelhead (O....

10 CFR 63.114 - Requirements for performance assessment.

Code of Federal Regulations, 2014 CFR

2014-01-01

... GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Technical Criteria Postclosure Performance Assessment § 63..., hydrology, and geochemistry (including disruptive processes and events) of the Yucca Mountain site, and the... disposal, and provide for the technical basis for parameter ranges, probability distributions, or bounding...

10 CFR 63.114 - Requirements for performance assessment.

Code of Federal Regulations, 2013 CFR

2013-01-01

... GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Technical Criteria Postclosure Performance Assessment § 63..., hydrology, and geochemistry (including disruptive processes and events) of the Yucca Mountain site, and the... disposal, and provide for the technical basis for parameter ranges, probability distributions, or bounding...

10 CFR 63.114 - Requirements for performance assessment.

Code of Federal Regulations, 2012 CFR

2012-01-01

... GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Technical Criteria Postclosure Performance Assessment § 63..., hydrology, and geochemistry (including disruptive processes and events) of the Yucca Mountain site, and the... disposal, and provide for the technical basis for parameter ranges, probability distributions, or bounding...

10 CFR 63.114 - Requirements for performance assessment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Technical Criteria Postclosure Performance Assessment § 63..., hydrology, and geochemistry (including disruptive processes and events) of the Yucca Mountain site, and the... disposal, and provide for the technical basis for parameter ranges, probability distributions, or bounding...

10 CFR 63.114 - Requirements for performance assessment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Technical Criteria Postclosure Performance Assessment § 63..., hydrology, and geochemistry (including disruptive processes and events) of the Yucca Mountain site, and the... disposal, and provide for the technical basis for parameter ranges, probability distributions, or bounding...

The Influence of Intensifying Irrigation on Glacier Mass Balances in High Mountain Asia

NASA Astrophysics Data System (ADS)

de Kok, R.; Tuinenburg, O.; Bonekamp, P. N. J.; Immerzeel, W. W.

2017-12-01

Melt water from snow and glaciers in High Mountain Asia provide a major source of water for millions of inhabitants in the downstream low lying plains. This densely populated region also hosts some of the largest areas of irrigated land in the world. Not only is the water from High Mountain Asia important as a source of irrigation water, the irrigation itself might also change the regional, and even global, climate by increasing atmospheric moisture and by cooling the surface through evapotranspiration. We explore the effect of irrigation in the region on the synoptic climate patterns in High Mountain Asia using the WRF regional climate model. By studying the changes in the energy balance, temperatures and precipitation, we assess how the changes in irrigation patterns may have contributed to the observed trends in mountain climates and associated glacier mass balances. Initial results show that the intensifying irrigation during the last decades causes an increase in summer snowfall in the mountains in Central Karakoram and Kunlun Shan, which are the regions where slight positive mass balances have been observed in recent years. A moisture tracking model confirms that the irrigated areas are a significant moisture source for summer precipitation in High Mountain Asia. These results thus suggest that irrigation may significantly influence glaciers in High Mountain Asia, especially in the regions of observed anomalous mass balance.

Slope Controls Grain Yield and Climatic Yield in Mountainous Yunnan province, China

NASA Astrophysics Data System (ADS)

Duan, X.; Rong, L.; Gu, Z.; Feng, D.

2017-12-01

Mountainous regions are increasingly vulnerable to food insecurity because of limited arable land, growing population pressure, and climate change. Development of sustainable mountain agriculture will require an increased understanding of the effects of environmental factors on grain and climatic yields. The objective of this study was to explore the relationships between actual grain yield, climatic yield, and environmental factors in a mountainous region in China. We collected data on the average grain yield per unit area in 119 counties in Yunnan province from 1985 to 2012, and chose 17 environmental factors for the same period. Our results showed that actual grain yield ranged from 1.43 to 6.92 t·ha-1, and the climatic yield ranged from -0.15 to -0.01 t·ha-1. Lower climatic yield but higher grain yield was generally found in central areas and at lower slopes and elevations in the western and southwestern counties of Yunnan province. Higher climatic yield but lower grain yield were found in northwestern parts of Yunnan province on steep slopes. Annual precipation and temperature had a weak influence on the climatic yield. Slope explained 44.62 and 26.29% of the variation in grain yield and climatic yield. The effects of topography on grain and climatic yields were greater than climatic factors. Slope was the most important environmental variable for the variability in climatic and grain yields in the mountainous Yunnan province due to the highly heterogeneous topographic conditions. Conversion of slopes to terraces in areas with higher climatic yields is an effective way to maintain grain production in response to climate variability. Additionally, soil amendments and soil and water conservation measures should be considered to maintain soil fertility and aid in sustainable development in central areas, and in counties at lower slopes and elevations in western and southwestern Yunnan province.

Recent and future climate suitability for whitebark pine mortality from mountain pine beetles varies across the western US

Treesearch

Polly C. Buotte; Jeffrey A. Hicke; Haiganoush K. Preisler; John T. Abatzoglou; Kenneth F. Raffa; Jesse A. Logan

2017-01-01

Recent mountain pine beetle outbreaks in whitebark pine forests have been extensive and severe. Understanding the climate influences on these outbreaks is essential for developing management plans that account for potential future mountain pine beetle outbreaks, among other threats, and informing listing decisions under the Endangered Species Act. Prior research has...

Numerical Modeling of Rocky Mountain Paleoglaciers - Insights into the Climate of the Last Glacial Maximum and the Subsequent Deglaciation

NASA Astrophysics Data System (ADS)

Leonard, E. M.; Laabs, B. J. C.; Plummer, M. A.

2014-12-01

Numerical modeling of paleoglaciers can yield information on the climatic conditions necessary to sustain those glaciers. In this study we apply a coupled 2-d mass/energy balance and flow model (Plummer and Phillips, 2003) to reconstruct local last glacial maximum (LLGM) glaciers and paleoclimate in ten study areas along the crest of the U.S. Rocky Mountains between 33°N and 49°N. In some of the areas, where timing of post-LLGM ice recession is constrained by surface exposure ages on either polished bedrock upvalley from the LLGM moraines or post-LLGM recessional moraines, we use the model to assess magnitudes and rates of climate change during deglaciation. The modeling reveals a complex pattern of LLGM climate. The magnitude of LLGM-to-modern climate change (temperature and/or precipitation change) was greater in both the northern (Montana) Rocky Mountains and southern (New Mexico) Rocky Mountains than in the middle (Wyoming and Colorado) Rocky Mountains. We use temperature depression estimates from global and regional climate models to infer LLGM precipitation from our glacier model results. Our results suggest a reduction of precipitation coupled with strongly depressed temperatures in the north, contrasted with strongly enhanced precipitation and much more modest temperature depression in the south. The middle Rocky Mountains of Colorado and Wyoming appear to have experienced a reduction in precipitation at the LLGM without the strong temperature depression of the northern Rocky Mountains. Preliminary work on modeling of deglaciation in the Sangre de Cristo Range in southern Colorado suggests that approximately half of the LLGM-to-modern climate change took place during the initial ~2400 years of deglaciation. If increasing temperature and changing solar insolation were the sole drivers of this initial deglaciation, then temperature would need to have risen by slightly more than 1°C/ky through this interval to account for the observed rate of ice recession.

Past and Future Climate Change Impacts on Mountain Forests on the Olympic Peninsula (Washington, USA)

NASA Astrophysics Data System (ADS)

Schwörer, C.; Fisher, D. M.; Gavin, D. G.; Temperli, C.; Bartlein, P. J.

2015-12-01

Mountain forest composition and distribution is strongly affected by temperature and is expected to shift to higher elevations with climate change. However, warmer winters will also lead to an upward shift of the snowline and a decrease in snowpack at lower and intermediate elevations. In the mountain ranges of Western North America, snowpack plays an important role in providing additional moisture during the dry summer months. It is therefore unclear if the projected climate change will lead to a rise of subalpine forest due to a longer growing season or a contraction due to drought stress. Since forest succession processes take place over decades and centuries we use LandClim, a dynamic vegetation model, to assess the impact of climate change on mountain forests on the Olympic Peninsula (Washington, USA). As a reality check we first simulate vegetation dynamics since the last Ice Age and compare model output with paleobotanical data from five natural archives that span the topographic and climatic gradients on the Peninsula. LandClim produces realistic present-day species compositions with respect to elevation and precipitation gradients. Moreover, the simulations of forest dynamics for the last 16,000 years generally agree with the pollen and macrofossil data. We then simulated mountain forests under future climate projections. As a result, our model indicates drastic changes in species composition with a replacement of mountain hemlock (Tsuga mertensiana) by more drought-resistant species such as subalpine fir (Abies lasiocarpa). On the drier, eastern side of the Peninsula, the model even suggests a lowering of timberline due to insufficient moisture availability in shallow alpine soils. Our results have important implications for ecosystem managers and stress the urgency of climate change mitigation.

Climate influences on whitebark pine mortality from mountain pine beetle in the Greater Yellowstone Ecosystem

Treesearch

Polly C. Buotte; Jeffrey A. Hicke; Haiganoush K. Preisler; John T. Abatzoglou; Kenneth F. Raffa; Jesse A. Logan

2016-01-01

Extensive mortality of whitebark pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western USA, primarily from mountain pine beetle but also from other threats such as white pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark pine mortality from mountain pine beetle...

Effects of climate change and wildfire on stream temperatures and salmonid thermal habitat in a mountain river network

Treesearch

Daniel J. Isaak; Charles H. Luce; Bruce E. Rieman; David E. Nagel; Erin E. Peterson; Dona L. Horan; Sharon Parkes; Gwynne L. Chandler

2010-01-01

Mountain streams provide important habitats for many species, but their faunas are especially vulnerable to climate change because of ectothermic physiologies and movements that are constrained to linear networks that are easily fragmented. Effectively conserving biodiversity in these systems requires accurate downscaling of climatic trends to local habitat conditions...

Understanding the science of climate change: Talking points - Impacts to western mountains and forests

Treesearch

Rachel Loehman

2009-01-01

Observed climate changes in the Western Mountains and Forests bioregion include increased seasonal, annual, minimum, and maximum temperatures, altered precipitation patterns, and a shift toward earlier timing of peak runoff. These climatic changes have resulted in widespread mortality in western forests, species range shifts and changes in phenology, productivity, and...

Impact of climate change on projected runoff from mountain snowpack of the King’s Rivershed in California

USDA-ARS?s Scientific Manuscript database

The Central Valley of California, like most dryland agricultural areas in the Southwest United States, relies heavily on winter snowpack for water resources. Projections of future climate in the Sierra Mountains of California calls for a warmer climate regime that will impact the snowpack in the Sie...

The Consortium for Integrated Climate Research in Western Mountains (CIRMOUNT)

Treesearch

Constance I. Millar

2004-01-01

I represent a nascent effort in western North America that is committed to improving integration of climate-related research and its societal implications. We go under the name of CIRMOUNT, that is, Consortium for Integrated Climate-Related Research in Western North American Mountains. In a sense, CIRMOUNT is a North American answer (in the affirmative) to Thomas...

Flat world versus real world : where is weathering the most important ?

NASA Astrophysics Data System (ADS)

Godderis, Yves; Maffre, Pierre; Ladant, Jean-Baptiste; Donnadieu, Yannick

2016-04-01

Mountain ranges are a key driver of the Earth climates. Acting on a large range of timescales, they modulate the atmospheric and oceanic circulations but also plays a crucial role in regulating the geological carbon cycle through their impacts on erosion and continental weathering. Since the 90's, there is an ongoing debate about the role of the mountain uplift on the long term global cooling of the Earth climate. Mountain ranges are thought to enhance silicate weathering and the associated CO2 consumption. But this has been repeatedly questioned in the recent years. Here we present a new method for modeling the spatial distribution of both physical erosion and coupled chemical weathering. The IPSL ocean-atmosphere model calculates the continental climate, which is used to force the erosion/weathering model. We first compare the global silicate weathering for two geographical configurations: the present-day world with mountain ranges, and a world where all mountains have been removed. Depending on the chosen formalism for silicate weathering and on the climate changes linked to the removal of mountains, it can be higher in the flat world than in the real world, or up to 5 times weaker. In the second part of the talk, we will explore the role of the Hercynian mountain range on the onset and demise of the late Paleozoic ice age, within the context of the Pangea assembly.

Methods for developing time-series climate surfaces to drive topographically distributed energy- and water-balance models

USGS Publications Warehouse

Susong, D.; Marks, D.; Garen, D.

1999-01-01

Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.

Projecting the future of an alpine ungulate under climate change scenarios.

PubMed

White, Kevin S; Gregovich, David P; Levi, Taal

2018-03-01

Climate change represents a primary threat to species persistence and biodiversity at a global scale. Cold adapted alpine species are especially sensitive to climate change and can offer key "early warning signs" about deleterious effects of predicted change. Among mountain ungulates, survival, a key determinant of demographic performance, may be influenced by future climate in complex, and possibly opposing ways. Demographic data collected from 447 mountain goats in 10 coastal Alaska, USA, populations over a 37-year time span indicated that survival is highest during low snowfall winters and cool summers. However, general circulation models (GCMs) predict future increase in summer temperature and decline in winter snowfall. To disentangle how these opposing climate-driven effects influence mountain goat populations, we developed an age-structured population model to project mountain goat population trajectories for 10 different GCM/emissions scenarios relevant for coastal Alaska. Projected increases in summer temperature had stronger negative effects on population trajectories than the positive demographic effects of reduced winter snowfall. In 5 of the 10 GCM/representative concentration pathway (RCP) scenarios, the net effect of projected climate change was extinction over a 70-year time window (2015-2085); smaller initial populations were more likely to go extinct faster than larger populations. Using a resource selection modeling approach, we determined that distributional shifts to higher elevation (i.e., "thermoneutral") summer range was unlikely to be a viable behavioral adaptation strategy; due to the conical shape of mountains, summer range was expected to decline by 17%-86% for 7 of the 10 GCM/RCP scenarios. Projected declines of mountain goat populations are driven by climate-linked bottom-up mechanisms and may have wide ranging implications for alpine ecosystems. These analyses elucidate how projected climate change can negatively alter population dynamics of a sentinel alpine species and provide insight into how demographic modeling can be used to assess risk to species persistence. © 2017 John Wiley & Sons Ltd.

Mountain peatlands range from CO2 sinks at high elevations to sources at low elevations: Implications for a changing climate

Treesearch

David J. Millar; David J. Cooper; Kathleen A. Dwire; Robert M. Hubbard; Joseph von Fischer

2016-01-01

Mountain fens found in western North America have sequestered atmospheric carbon dioxide (CO2) for millennia, provide important habitat for wildlife, and serve as refugia for regionally-rare plant species typically found in boreal regions. It is unclear how Rocky Mountain fens are responding to a changing climate. It is possible that fens found at lower elevations may...

Alpine infrastructure in Central Europe: integral evaluation of wastewater treatment systems at mountain refuges.

PubMed

Weissenbacher, N; Mayr, E; Niederberger, T; Aschauer, C; Lebersorger, S; Steinbacher, G; Haberl, R

2008-01-01

Planning, construction and operation of onsite wastewater treatment systems at mountain refuges is a challenge. Energy supply, costly transport, limited water resources, unfavourable climate and load variations are only some of the problems that have to be faced. Additionally, legal regulations are different between and even within countries of the Alps. To ensure sustainability, integrated management of the alpine infrastructure management is needed. The energy and water supply and the wastewater and waste disposal systems and the cross-relations between them were analysed for 100 mountain refuges. Wastewater treatment is a main part of the overall 'mountain refuge' system. The data survey and first analyses showed the complex interaction of the wastewater treatment with the other infrastructure. Main criteria for reliable and efficient operation are training, technical support, user friendly control and a relatively simple system set up. Wastewater temperature, alkalinity consumption and high peak loads have to be considered in the planning process. The availability of power in terms of duration and connexion is decisive for the choice of the system. Further, frequency fluctuations may lead to damages to the installed aerators. The type of water source and the type of sanitary equipment influence the wastewater quantity and quality. Biosolids are treated and disposed separately or together with primary or secondary sludge from wastewater treatment dependent on the legal requirements. IWA Publishing 2008.

Climate and weather influences on spatial temporal patterns of mountain pine beetle populations in Washington and Oregon

Treesearch

Haiganoush K. Preisler; Jeffrey A. Hicke; Alan A. Ager; Jane L. Hayes

2012-01-01

Widespread outbreaks of mountain pine beetle in North America have drawn the attention of scientists, forest managers, and the public. There is strong evidence that climate change has contributed to the extent and severity of recent outbreaks. Scientists are interested in quantifying relationships between bark beetle population dynamics and trends in climate. Process...

Declining water yield from forested mountain watersheds in response to climate change and forest mesophication

Treesearch

Peter V. Caldwell; Chelcy F. Miniat; Katherine J. Elliott; Wayne. T. Swank; Steven T. Brantley; Stephanie H. Laseter

2016-01-01

Climate change and forest disturbances are threatening the ability of forested mountain watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Here we used 76 years of water yield, climate, and field plot vegetation measurements in six unmanaged, reference watersheds in the southern...

Climate change, aquatic ecosystems, and fishes in the Rocky Mountain West: implications and alternatives for management

Treesearch

Bruce E. Rieman; Daniel J. Isaak

2010-01-01

Anthropogenic climate change is rapidly altering aquatic ecosystems across the Rocky Mountain West and may detrimentally impact populations of sensitive species that are often the focus of conservation efforts. The objective of this report is to synthesize a growing literature on these topics to address the following questions: (1) What is changing in climate and...

The importance of geomorphic and hydrologic factors in shaping the sensitivity of alpine/subalpine lake volumes to shifts in climate

NASA Astrophysics Data System (ADS)

Mercer, J.; Liefert, D. T.; Shuman, B. N.; Befus, K. M.; Williams, D. G.; Kraushaar, B.

2017-12-01

Alpine and subalpine lakes are important components of the hydrologic cycle in mountain ecosystems. These lakes are also highly sensitive to small shifts in temperature and precipitation. Mountain lake volumes and their contributions to mountain hydrology may change in response to even minor declines in snowpack or increases in temperature. However, it is still not clear to what degree non-climatic factors, such as geomorphic setting and lake geometry, play in shaping the sensitivity of high elevation lakes to climate change. We investigated the importance of lake geometry and groundwater connectivity to mountain lakes in the Snowy Range, Wyoming using a combination of hydrophysical and hydrochemical methods, including stable water isotopes, to better understand the role these factors play in controlling lake volume. Water isotope values in open lakes were less sensitive to evaporation compared to those in closed basin lakes. Lake geometry played an important role, with wider, shallower lakes being more sensitive to evaporation over time. Groundwater contributions appear to play only a minor role in buffering volumetric changes to lakes over the growing season. These results confirm that mountain lakes are sensitive to climate factors, but also highlight a significant amount of variability in that sensitivity. This research has implications for water resource managers concerned with downstream water quantity and quality from mountain ecosystems, biologists interested in maintaining aquatic biodiversity, and paleoclimatologists interested in using lake sedimentary information to infer past climate regimes.

Amphibians in the climate vise: loss and restoration of resilience of montane wetland ecosystems in the western US

USGS Publications Warehouse

Ryan, Maureen E.; Palen, Wendy J.; Adams, Michael J.; Rochefort, Regina M.

2014-01-01

Wetlands in the remote mountains of the western US have undergone two massive ecological “experiments” spanning the 20th century. Beginning in the late 1800s and expanding after World War II, fish and wildlife managers intentionally introduced millions of predatory trout (primarily Oncorhynchus spp) into fishless mountain ponds and lakes across the western states. These new top predators, which now occupy 95% of large mountain lakes, have limited the habitat distributions of native frogs, salamanders, and wetland invertebrates to smaller, more ephemeral ponds where trout do not survive. Now a second “experiment” – anthropogenic climate change – threatens to eliminate many of these ephemeral habitats and shorten wetland hydroperiods. Caught between climate-induced habitat loss and predation from introduced fish, native mountain lake fauna of the western US – especially amphibians – are at risk of extirpation. Targeted fish removals, guided by models of how wetlands will change under future climate scenarios, provide innovative strategies for restoring resilience of wetland ecosystems to climate change.

Changes in the Mountain Cryosphere and Potential Risks to Downstream Communities: Insights from the Indian Himalayan Region

NASA Astrophysics Data System (ADS)

Allen, Simon; Ballesteros, Juan Antonio; Huggel, Christian; Linsbauer, Andreas; Mal, Suraj; Singh Rana, Ranbir; Singh Randhawa, Surjeet; Ruiz-Villanueva, Virginia; Salzmann, Nadine; Singh Samant, Sher; Stoffel, Markus

2017-04-01

Mountain environments around the world are often considered to be amongst the most sensitive to the impacts of climate change. For people living in mountain communities, there are clear challenges to be faced as their livelihoods and subsistence are directly dependent on their surrounding natural environment. But what of the wider implications for societies and large urban settlements living downstream - why should they care about the climate-driven changes occurring potentially hundreds of kilometers away in the snow and ice capped mountains? In this contribution we address this question, drawing on studies and experiences gained within joint Indo-Swiss research collaborations focused on the Indian Himalayan states of Himachal Pradesh and Uttarakhand. With the Intergovernmental Panel on Climate Change currently embarking on the scoping of their 6th Assessment Cycle, which includes a planned Special Report on Oceans and the Cryosphere, this contribution provides a timely reminder of the importance of mountain regions, and potential far-reaching consequences of changes in the mountain cryosphere. Our studies highlight several key themes which link the mountain environment to the lowland populated areas, including the role of the mountain cryosphere as a water source, far-reaching hazards and disasters that can originate from mountain regions, the role of mountains in providing essential ecosystem services, the economic importance of tourism in mountain regions, and the importance of transportation routes which pass through mountain environments. These themes are intricately linked, as for example demonstrated during the 2013 Uttarakhand flood disaster where many of the approximately 6000 fatalities were tourists visiting high mountain pilgrimage sites. As a consequence of the disaster, tourists stayed away during subsequent seasons with significant economic impacts felt across the State. In Himachal Pradesh, a key national transportation corridor is the Rohtang pass and tunnel, linking Kullu with Lahual and Spiti districts in the north. Our studies have shown that this corridor is threatened by a range of climate related hazards, including debris flows, flash floods, and snow avalanches, highlighting the need to consider climate change scenarios to ensure the long-term sustainability of vital transportation networks in mountain regions. Often a transboundary perspective is required. For example, in 2000 a landslide dammed lake located in Tibet breached, causing the loss of at least 156 lives in the Indian district of Kinnaur located 100 km downstream, with infrastructural damage and loss of revenue estimated at up to US 222 million. Considering the wide-ranging ways in which downstream societies interact with and depend upon mountain environments, systematic monitoring and assessment of changes in the high mountain cryosphere is essential to ensure that adaptation decisions are evidence-based, and well supported by latest scientific understanding.

Climate along the crest of the US Rocky Mountains during the last glaciation: preliminary insights from numerical modeling of paleoglaciers

NASA Astrophysics Data System (ADS)

Leonard, E. M.; Laabs, B. J.; Plummer, M. A.; Huss, E.; Spiess, V. M.; Mackall, B. T.; Jacobsen, R. E.; Quirk, B.

2012-12-01

Climate conditions at the time of the local Last Glacial Maximum (LGM) in the US Rocky Mountains were assessed using a 2-d coupled glacier energy/mass-balance and ice-flow model (Plummer and Phillips, 2003). The model was employed to understand the conditions that would be necessary to sustain valley glaciers and small mountain icecaps at their maximum extents in eight areas distributed along the crest of the range from northern New Mexico (35.8oN) to northern Montana (48.6oN). For each setting, model experiments yield a set of temperature and precipitation combinations that may have accompanied the local LGM. If the results of global and regional climate models are used to constrain temperature depression estimates from our model experiments, the following precipitation pattern emerges for the local LGM. In the northern Rocky Mountains in Montana and northern Wyoming, model results suggest a strong reduction in precipitation of 50% or more. In the central Rocky Mountains of southern Wyoming and Colorado, precipitation appears to have been 50-90% of modern. By contrast, precipitation appears to have been strongly enhanced in the southern Rocky Mountains of New Mexico. These results are broadly consistent with a pattern of precipitation observed in global and regional climate simulations of the LGM in the western U.S., in which precipitation was reduced in the northern Rocky Mountains but increased in the southern Rocky Mountains. This pattern may reflect a southward displacement of mean position the Pacific Jet Stream in western North America during and possibly following the LGM.

Investigating Downscaling Methods and Evaluating Climate Models for Use in Estimating Regional Water Resources in Mountainous Regions under Changing Climatic Conditions

NASA Technical Reports Server (NTRS)

Frei, Allan; Nolin, Anne W.; Serreze, Mark C.; Armstrong, Richard L.; McGinnis, David L.; Robinson, David A.

2004-01-01

The purpose of this three-year study is to develop and evaluate techniques to estimate the range of potential hydrological impacts of climate change in mountainous areas. Three main objectives are set out in the proposal. (1) To develop and evaluate transfer functions to link tropospheric circulation to regional snowfall. (2) To evaluate a suite of General Circulation Models (GCMs) for use in estimating synoptic scale circulation and the resultant regional snowfall. And (3) to estimate the range of potential hydrological impacts of changing climate in the two case study areas: the Upper Colorado River basin, and the Catskill Mountains of southeastern New York State. Both regions provide water to large populations.

Snowpack sensitivity to perturbed climate changes in alpine catchements

USDA-ARS?s Scientific Manuscript database

There is great interest in ascertaining the degree of climate change necessary to induce substantial changes in snow accumulation and ablation processes in mountain headwater catchments. Therefore, the response of mountain snow hydrology to changes in air temperature and precipitation was examined ...

Mountain pine beetle seasonal timing and constraints to bivoltinism (A comment on Mitton and Ferrenberg, "Mountain Pine Beetle Develops an Unprecedented Summer Generation in Response to Climate Warming")

Treesearch

Barbara J. Bentz; James A. Powell

2014-01-01

Mountain pine beetle tree colonization typically occurs in July and August, with completion of a generation one (univoltinism) or two (semivoltinism) years later. In a 2012 publication, Mitton and Ferrenberg suggested that climate change resulted in an unprecedented generation between June and September (a summer generation), with a concomitant shift to two...

Sensitivity of alpine watersheds to global change

NASA Astrophysics Data System (ADS)

Zierl, B.; Bugmann, H.

2003-04-01

Mountains provide society with a wide range of goods and services, so-called mountain ecosystem services. Besides many others, these services include the most precious element for life on earth: fresh water. Global change imposes significant environmental pressure on mountain watersheds. Climate change is predicted to modify water availability as well as shift its seasonality. In fact, the continued capacity of mountain regions to provide fresh water to society is threatened by the impact of environmental and social changes. We use RHESSys (Regional HydroEcological Simulation System) to analyse the impact of climate as well as land use change (e.g. afforestation or deforestation) on hydrological processes in mountain catchments using sophisticated climate and land use scenarios. RHESSys combines distributed flow modelling based on TOPMODEL with an ecophysiological canopy model based on BIOME-BGC and a climate interpolation scheme based on MTCLIM. It is a spatially distributed daily time step model designed to solve the coupled cycles of water, carbon, and nitrogen in mountain catchments. The model is applied to various mountain catchments in the alpine area. Dynamic hydrological and ecological properties such as river discharge, seasonality of discharge, peak flows, snow cover processes, soil moisture, and the feedback of a changing biosphere on hydrology are simulated under current as well as under changed environmental conditions. Results of these studies will be presented and discussed. This project is part of an over overarching EU-project called ATEAM (acronym for Advanced Terrestrial Ecosystem Analysis and Modelling) assessing the vulnerability of European ecosystem services.

The future of subalpine forests in the Southern Rocky Mountains: Trajectories for Pinus aristata genetic lineages

Treesearch

Sparkle L. Malone; Anna W. Schoettle; Jonathan D. Coop

2018-01-01

Like many other high elevation alpine tree species, Rocky Mountain bristlecone pine (Pinus aristata Engelm.) may be particularly vulnerable to climate change. To evaluate its potential vulnerability to shifts in climate, we defined the suitable climate space for each of four genetic lineages of bristlecone pine and for other subalpine tree species in close proximity to...

Climate change and special habitats in the Blue Mountains: Riparian areas, wetlands, and groundwater-dependent ecosystems [Chapter 7

Treesearch

Kathleen A. Dwire; Sabine Mellmann-Brown

2017-01-01

In the Blue Mountains, climate change is likely to have significant, long-term implications for freshwater resources, including riparian areas, wetlands (box 7.1), and groundwater-dependent ecosystems (GDEs, box 7.2). Climate change is expected to cause a transition from snow to rain, resulting in diminished snowpack and shifts in streamflow to earlier in the season (...

Evidence of climate change impact on stream low flow from the tropical mountain rainforest watershed in Hainan Island, China

Treesearch

Z. Zhou; Y. Ouyang; Z. Qiu; G. Zhou; M. Lin; Y. Li

2017-01-01

Stream low flow estimates are central to assessing climate change impact, water resource management, and ecosystem restoration. This study investigated the impacts of climate change upon stream low flows from a rainforest watershed in Jianfengling (JFL) Mountain, Hainan Island, China, using the low flow selection method as well as the frequency and probability analysis...

Tectonics of the central Andes

NASA Technical Reports Server (NTRS)

Bloom, Arthur L.; Isacks, Bryan L.; Fielding, Eric J.; Fox, Andrew N.; Gubbels, Timothy L.

1989-01-01

Acquisition of nearly complete coverage of Thematic Mapper data for the central Andes between about 15 to 34 degrees S has stimulated a comprehensive and unprecedented study of the interaction of tectonics and climate in a young and actively developing major continental mountain belt. The current state of the synoptic mapping of key physiographic, tectonic, and climatic indicators of the dynamics of the mountain/climate system are briefly reviewed.

Thermal regimes of Rocky Mountain lakes warm with climate change

PubMed Central

Roberts, James J.

2017-01-01

Anthropogenic climate change is causing a wide range of stresses in aquatic ecosystems, primarily through warming thermal conditions. Lakes, in response to these changes, are experiencing increases in both summer temperatures and ice-free days. We used continuous records of lake surface temperature and air temperature to create statistical models of daily mean lake surface temperature to assess thermal changes in mountain lakes. These models were combined with downscaled climate projections to predict future thermal conditions for 27 high-elevation lakes in the southern Rocky Mountains. The models predict a 0.25°C·decade-1 increase in mean annual lake surface temperature through the 2080s, which is greater than warming rates of streams in this region. Most striking is that on average, ice-free days are predicted to increase by 5.9 days ·decade-1, and summer mean lake surface temperature is predicted to increase by 0.47°C·decade-1. Both could profoundly alter the length of the growing season and potentially change the structure and function of mountain lake ecosystems. These results highlight the changes expected of mountain lakes and stress the importance of incorporating climate-related adaptive strategies in the development of resource management plans. PMID:28683083

Thermal regimes of Rocky Mountain lakes warm with climate change

USGS Publications Warehouse

Roberts, James J.; Fausch, Kurt D.; Schmidt, Travis S.; Walters, David M.

2017-01-01

Anthropogenic climate change is causing a wide range of stresses in aquatic ecosystems, primarily through warming thermal conditions. Lakes, in response to these changes, are experiencing increases in both summer temperatures and ice-free days. We used continuous records of lake surface temperature and air temperature to create statistical models of daily mean lake surface temperature to assess thermal changes in mountain lakes. These models were combined with downscaled climate projections to predict future thermal conditions for 27 high-elevation lakes in the southern Rocky Mountains. The models predict a 0.25°C·decade-1increase in mean annual lake surface temperature through the 2080s, which is greater than warming rates of streams in this region. Most striking is that on average, ice-free days are predicted to increase by 5.9 days ·decade-1, and summer mean lake surface temperature is predicted to increase by 0.47°C·decade-1. Both could profoundly alter the length of the growing season and potentially change the structure and function of mountain lake ecosystems. These results highlight the changes expected of mountain lakes and stress the importance of incorporating climate-related adaptive strategies in the development of resource management plans.

Thermal regimes of Rocky Mountain lakes warm with climate change.

PubMed

Roberts, James J; Fausch, Kurt D; Schmidt, Travis S; Walters, David M

2017-01-01

Anthropogenic climate change is causing a wide range of stresses in aquatic ecosystems, primarily through warming thermal conditions. Lakes, in response to these changes, are experiencing increases in both summer temperatures and ice-free days. We used continuous records of lake surface temperature and air temperature to create statistical models of daily mean lake surface temperature to assess thermal changes in mountain lakes. These models were combined with downscaled climate projections to predict future thermal conditions for 27 high-elevation lakes in the southern Rocky Mountains. The models predict a 0.25°C·decade-1 increase in mean annual lake surface temperature through the 2080s, which is greater than warming rates of streams in this region. Most striking is that on average, ice-free days are predicted to increase by 5.9 days ·decade-1, and summer mean lake surface temperature is predicted to increase by 0.47°C·decade-1. Both could profoundly alter the length of the growing season and potentially change the structure and function of mountain lake ecosystems. These results highlight the changes expected of mountain lakes and stress the importance of incorporating climate-related adaptive strategies in the development of resource management plans.

Regional-Scale Climate Change: Observations and Model Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bradley, Raymond S; Diaz, Henry F

2010-12-14

This collaborative proposal addressed key issues in understanding the Earth's climate system, as highlighted by the U.S. Climate Science Program. The research focused on documenting past climatic changes and on assessing future climatic changes based on suites of global and regional climate models. Geographically, our emphasis was on the mountainous regions of the world, with a particular focus on the Neotropics of Central America and the Hawaiian Islands. Mountain regions are zones where large variations in ecosystems occur due to the strong climate zonation forced by the topography. These areas are particularly susceptible to changes in critical ecological thresholds, andmore » we conducted studies of changes in phonological indicators based on various climatic thresholds.« less

Geomorphological Controls on Fluvial Organic Carbon Storage in Wood and Soil in the Olympic, Cascade, and Rocky Mountains

NASA Astrophysics Data System (ADS)

Scott, D.; Wohl, E.

2017-12-01

The terrestrial organic carbon (OC) pool plays a major role in impacting global climate through the storage and potential release of carbon. In particular, areas of high net primary productivity, such as mountainous regions, and high spatial complexity, such as mountain river floodplains, show potential to act as both strong OC reservoirs and potential OC emitters in a changing climate. We focus on mountain rivers as potential hot swaths of OC storage and, accordingly, as places where land management to retain OC on the landscape may be especially impactful. Mountain river OC storage magnitude and age is a function of the soil and geomorphologic conditions at a reach scale, which are in turn determined by broader characteristics, such as climate, ecology, and tectonics. We present field data on OC storage in soil and wood from three mountain ranges across the western U.S.: the Wind River Range in Wyoming and the Olympic and Central Cascade Ranges in Washington. While the Big Sandy River basin in the Wind River Range exhibits relatively low relief, a semi-arid climate, and a fire-mediated disturbance regime, the Middle Fork Snoqualmie basin in the Cascades and the Sitkum and South Fork Calawah basins in the Olympics exhibit high relief and a humid climate. In contrast to the Olympics, the study basin in the Cascades exhibits strong longitudinal disconnectivity in the form of glaciogenic lakes, whereas the study basins in the Olympics lack large depositional zones that can store sediment for long periods of time. With our expansive dataset of OC storage magnitude and age in downed wood and soil from these three disparate regions, covering a wide range of tectonic, geomorphic, climatic, and ecologic variability, we are able to evaluate both the magnitude and age of the mountain river carbon pool as well as the factors that control that magnitude and age. We present a statistical model that illuminates the dominant controls on the magnitude and age of OC storage in mountain rivers. Using this, we broadly examine mountain river carbon storage dynamics with the goal of allowing land managers to prioritize and focus management efforts to retain OC on the landscape.

Noble Gas Proxy Evidence Of Holocene Climate Fluctuations In The Elwha Watershed, Olympic Mountains, Washington

EPA Science Inventory

Paleotempertures retrieved from the groundwater archives in the largest watershed (≈800 km2) in the Olympic Mountains suggest asynchronous Olympic Peninsula climate responses during the Everson interstade period after the last continental glacial maximum. Dissolved noble gases fr...

Palaeoglaciology of the Central European Uplands - a link between the former ice masses over the Alps and Scandinavia

NASA Astrophysics Data System (ADS)

Hauzenberger, B.; Fickert, T.

2009-04-01

The Central European Uplands are located northeast of the Alps along the western edge of the Czech border. A horseshoe shaped range of low mountains contains the Bavarian Forest Mountains, the Fichtel Mountains, the Erz Mountains and the Giant Mountains, with highest summit altitudes ranging from 1051 m a.s.l. (Fichtel Mountains) to 1603 m a.s.l. (Giant Mountains). The location north of the Alps makes these mountains highly interesting as a possible link between the Scandinavian ice sheet and the Alps. Although the glacial traces of the Central European Uplands have been investigated for more than 100 years, the glacial history is still elusive. While the highest mountains (the Bavarian Forest and the Giant Mountains) hold evidence of valley glaciers, the lower mountains (the Fichtel and the Erz Mountains) lack unambiguous glacial traces. As a first step towards a palaeoglaciological reconstruction for the Central European Uplands, we present a digital map of glacier termini with elevation data from the SRTM elevation model, compiled from previous investigations of the area. The glacial map of the Central European Uplands presents the pattern of glacial traces over an extensive area in central Europe and forms the basis for reconstructing the extent of former glaciers. We compare the glacial evidence with modern day climate data (from the high resolution WorldClim database), from which we can estimate the climate change needed to produce Central European Upland glaciers. The glacial traces of the Central European Uplands hold information on past climate of the region and this may be a key to link the glacial record of the Alps with the Scandinavian ice sheet.

The effect of warmer winters on the demography of an outbreak insect is hidden by intraspecific competition.

PubMed

Goodsman, Devin W; Grosklos, Guenchik; Aukema, Brian H; Whitehouse, Caroline; Bleiker, Katherine P; McDowell, Nate G; Middleton, Richard S; Xu, Chonggang

2018-05-29

Warmer climates are predicted to increase bark beetle outbreak frequency, severity, and range. Even in favorable climates, however, outbreaks can decelerate due to resource limitation, which necessitates the inclusion of competition for limited resources in analyses of climatic effects on populations. We evaluated several hypotheses of how climate impacts mountain pine beetle reproduction using an extensive 9-year dataset, in which nearly 10,000 trees were sampled across a region of approximately 90,000 km 2 , that was recently invaded by the mountain pine beetle in Alberta, Canada. Our analysis supports the hypothesis of a positive effect of warmer winter temperatures on mountain pine beetle overwinter survival and provides evidence that the increasing trend in minimum winter temperatures over time in North America is an important driver of increased mountain pine beetle reproduction across the region. Although we demonstrate a consistent effect of warmer minimum winter temperatures on mountain pine beetle reproductive rates that is evident at the landscape and regional scales, this effect is overwhelmed by the effect of competition for resources within trees at the site level. Our results suggest that detection of the effects of a warming climate on bark beetle populations at small spatial scales may be difficult without accounting for negative density dependence due to competition for resources. © 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Carbon and oxygen isotope signatures in conifers from the Swiss National Park

NASA Astrophysics Data System (ADS)

Churakova (Sidorova), Olga; Saurer, Matthias; Siegwolf, Rolf; Bryukhanova, Marina; Bigler, Christof

2015-04-01

Our study investigates the physiological response and plasticity of trees under climatic changes for larch (Larix decidua) and mountain pine (Pinus mugo var. uncinata) in the Swiss National Park.This research was done in the context of investigation tree mortality and their potential to survive under the harsh mountainous conditions. For the stable isotope analysis we selected four mountain pine and four larch trees from each a south- and north-facing slope. Oxygen isotope ratios can give insight into water sources and evaporative processes. To understand the differential response of mountain pine and larch to short-term climatic changes we measured 18O/16O in water extracted from twigs and needles as well as soil samples for each species at both sites. The seasonal variabilities in 18O/16O needles and twigs of mountain pine and larch trees as well as soil samples were related to changes in climate conditions from end of May until middle of October. To reveal the main climatic factors driving tree growth of pine and larch trees in the long-term, tree-ring width chronologies were built and bulk 18O/16O, 13C/12C wood chronologies were analyzed and correlated with climatic parameters over the last 100 years. The results indicate a strong influence of spring and summer temperatures for larch trees, while variation of spring and summer precipitations is more relevant for mountain pine trees. This work is supported by the Swiss National Science Foundation, Marie-Heim Vögtlin Program PMPDP-2 145507

Glacier melt buffers river runoff in the Pamir Mountains

NASA Astrophysics Data System (ADS)

Pohl, Eric; Gloaguen, Richard; Andermann, Christoff; Knoche, Malte

2017-03-01

Newly developed approaches based on satellite altimetry and gravity measurements provide promising results on glacier dynamics in the Pamir-Himalaya but cannot resolve short-term natural variability at regional and finer scale. We contribute to the ongoing debate by upscaling a hydrological model that we calibrated for the central Pamir. The model resolves the spatiotemporal variability in runoff over the entire catchment domain with high efficiency. We provide relevant information about individual components of the hydrological cycle and quantify short-term hydrological variability. For validation, we compare the modeled total water storages (TWS) with GRACE (Gravity Recovery and Climate Experiment) data with a very good agreement where GRACE uncertainties are low. The approach exemplifies the potential of GRACE for validating even regional scale hydrological applications in remote and hard to access mountain regions. We use modeled time series of individual hydrological components to characterize the effect of climate variability on the hydrological cycle. We demonstrate that glaciers play a twofold role by providing roughly 35% of the annual runoff of the Panj River basin and by effectively buffering runoff both during very wet and very dry years. The modeled glacier mass balance (GMB) of -0.52 m w.e. yr-1 (2002-2013) for the entire catchment suggests significant reduction of most Pamiri glaciers by the end of this century. The loss of glaciers and their buffer functionality in wet and dry years could not only result in reduced water availability and increase the regional instability, but also increase flood and drought hazards.