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Future changes in the climate system could have significant impacts on the natural environment and human activities, which in turn affect changes in the climate system. In the interaction between natural and human systems under climate change conditions, land use is one of the elements that play an essential role. Future climate change will affect the availability of water and food, which may impact land-use change. On the other hand, human land-use change can affect the climate system through bio-geophysical and bio-geochemical effects. To investigate these interrelationships, we developed MIROC-INTEG1 (MIROC INTEGrated terrestrial model version 1), an integrated model that combines the global climate model MIROC (Model for Interdisciplinary Research on Climate) with water resources, crop production, land ecosystem, and land use models. In this paper, we introduce the details and interconnections of the sub-models of MIROC-INTEG1, compare historical simulations with observations, and identify the various interactions between sub-models. MIROC-INTEG1 makes it possible to quantitatively evaluate the feedback processes or nexus between climate, water resources, crop production, land use, and ecosystem, and to assess the risks, trade-offs and co-benefits associated with future climate change and prospective mitigation and adaptation policies. [ABSTRACT FROM AUTHOR]

The mountain cryosphere of mainland Europe is recognized to have important impacts on a range of environmental processes. In this paper, we provide an overview on the current knowledge on snow, glacier, and permafrost processes, as well as their past, current, and future evolution. We additionally provide an assessment of current cryosphere research in Europe and point to the different domains requiring further research. Emphasis is given to our understanding of climate-cryosphere interactions, cryosphere controls on physical and biological mountain systems, and related impacts. By the end of the century, Europe's mountain cryosphere will have changed to an extent that will impact the landscape, the hydrological regimes, the water resources, and the infrastructure. The impacts will not remain confined to the mountain area but also affect the downstream lowlands, entailing a wide range of socioeconomical consequences. European mountains will have a completely different visual appearance, in which low- and mid-range-altitude glaciers will have disappeared and even large valley glaciers will have experienced significant retreat and mass loss. Due to increased air temperatures and related shifts from solid to liquid precipitation, seasonal snow lines will be found at much higher altitudes, and the snow season will be much shorter than today. These changes in snow and ice melt will cause a shift in the timing of discharge maxima, as well as a transition of runoff regimes from glacial to nival and from nival to pluvial. This will entail significant impacts on the seasonality of high-altitude water availability, with consequences for water storage and management in reservoirs for drinking water, irrigation, and hydropower production. Whereas an upward shift of the tree line and expansion of vegetation can be expected into current periglacial areas, the disappearance of permafrost at lower altitudes and its warming at higher elevations will likely result in mass movements and process chains beyond historical experience. Future cryospheric research has the responsibility not only to foster awareness of these expected changes and to develop targeted strategies to precisely quantify their magnitude and rate of occurrence but also to help in the development of approaches to adapt to these changes and to mitigate their consequences. Major joint efforts are required in the domain of cryospheric monitoring, which will require coordination in terms of data availability and quality. In particular, we recognize the quantification of high-altitude precipitation as a key source of uncertainty in projections of future changes. Improvements in numerical modeling and a better understanding of process chains affecting high-altitude mass movements are the two further fields that - in our view - future cryospheric research should focus on. [ABSTRACT FROM AUTHOR]

Hydrological regimes of the Arctic have been of focal interest due the region's susceptibility to climate variability/change and resource development (eg, oil and gas, hydropower). Not only are the timing and magnitude of hydrological processes affected by cold-region processes that are thermally sensitive (snow, ice, permafrost), especially in a warming climate, but large-scale alterations of flow regimes via damming of rivers have been shown to potentially be significant disruptors of natural flow regimes and related aquatic ecosystems of Arctic rivers. The natural flow paradigm established explicit linkages between the flow regime and lotic ecosystem structure, function, and diversity. Riverine communities have adapted to variability in magnitude, timing, and predictability of key hydrograph components, such as high- and low-flow periods. Previous research has explored the significance of these and other key variables for hydro-ecological research and environmental flow needs (EFN) recommendations. EFN research historically focused on protection goals of maintaining minimum instream flows to sustain fish species of interest. It has become clear that this approach may fail to protect all components of the river and floodplain ecosystem. This is especially true for cold-climate countries where flow regimes are typically characterized by winter low flows during the ice-covered period, extreme water levels generated with the influence of ice jamming during the spring ice breakup, followed by high spring/summer flows during the open-water period.In light of increasing development pressures and projected climate change impacts on water availability, both timing and magnitude, there is a growing need to incorporate environmental flows into water sustainability frameworks for cold regions of the globe in order to sustain ecosystems. The goal of this paper is twofold: present an overview of environmental flows for the Arctic region, with a focus on North America; and ii) present the novel Cold-regions Hydrological Indicators of Change (CHIC), which can provide the basis for the assessment of EFN and climate change assessments in cold-region river ecosystems. [ABSTRACT FROM AUTHOR]

Climate change has already caused major effects in agricultural production and derived earnings on farming income worldwide. The farming areas in southeast Mediterranean are expected to incur production losses due to temperature increase, less precipitation volume and frequent drought occurrences. Such an example may be traced in Lake Karla watershed, in Central Greece, where intensified agricultural production is highly dependent on surface and (mainly) groundwater irrigation. The particular feature of Lake Karla watershed is the current refiling of a large part of the former lake aiming at environmental restoration and sustainable irrigation patterns. In this paper, we attempt to assess the climate change effects in farming produce of various crops cultivated in Lake Karla watershed by adopting mild, middle and severe climate projections on the period 2006-2100. The climate change projections are conducted through the downscaling of the IPCC's Representative Concentration Pathways (RCPs) based on monthly meteorological data from 1960-2005. We also adopt different scenarios of agricultural water demand depending on separate and conjunctive surface and groundwater use as well as cropping pattern variations. The Water Evaluation and Planning System (WEAP) tool is employed to assess water balance within the selected scenarios while the CROPWAT software is introduced to account for the relevant productivity effects. A linear economic modeling is also employed to measure the profit alterations occurring due to climate change in the farmlands. The findings suggest that the reinforcement of surface water supply coupled with new cropping patterns may considerably offset climate change impacts and economic losses of agricultural income in Lake Karla watershed. Notwithstanding the major impacts of climate change in agriculture, it is however noticed that different interventions in irrigation volume (regarding technical measures increasing the efficiency in water use) and techniques may mitigate the impacts. More detailed information on the current irrigation demand and sources per farming area is anticipated to better clarify the relations between climate change and irrigation interventions in the study area. Finally, useful outcomes occur about modeling uncertainties carried by climate change hypotheses. [ABSTRACT FROM AUTHOR]

As a typical alpine marsh wetland on the Qinghai-Tibet Plateau, the Zoige Wetland plays an important role in the water source recharge of Yellow River. Meanwhile, it is more sensitive to climate change. Therefore, it is necessary to study the hydrological cycle of Zoige Wetland and the impact of climate change, which will also provide important support and reference for the study of hydrological process, and protection of wetland water resources in Alpine areas. Based on the distributed hydrological model, this paper analyzed the runoff process in the Zoige wetland basin, and explored the trend of runoff variation in the Zoige wetland basin under different climate change scenarios in the next 30 years from 2020 to 2050. The impact of climate change on wetland runoff were also discussed. Results showed that the runoff in the Zoige Wetland basin decreased under the future climate change scenario. The rate of runoff reduction was the largest in Machu station, followed by Zoige station, and finally Tangke station. The reduction in non-flooding runoff is significantly higher than that in the flood season. The runoff during non-flood season in the Zoige Wetland basin from 2020 to 2050 will decrease by more than 25% in the future climate change scenario. The sharp decline in non-flooded runoff may have an impact on the protection of the Zoige Wetland and the management of water resources in the middle reaches of the Yellow River and downstream areas. This poses more stringent requirements for the protection of the Zoige Wetland in response to future climate change. Under future climate change scenarios, how to strengthen the management and protection of wetland water resources and prevent the degradation and atrophy of wetlands is the issue we need to further discuss and consider. [ABSTRACT FROM AUTHOR]

Human activities and climate change are two key factors influencing the variation of the total amount of available surface and groundwater, hereafter termed water resources. Quantitatively separating their impacts remains a challenge. To this end, we used time-varying Budyko-type equations and a hierarchical Bayesian model in this paper to separate their impacts in 31 provincial-level divisions of China. The time-varying Budyko-type equations treat the Budyko equation parameter w as a variable, which depends on human activities (represented by per capita gross regional production) and climate change (represented by temperature and precipitation). The hierarchical model quantifies the uncertainty of parameters and the interrelation between covariates across regions in China. The results show that the time-varying Budyko-type equation can improve the fitting capability for water resources in China. The hierarchical Bayesian model, which considered spatial dependence, reduced the uncertainty of the parameters compared to spatially independent counterparts. For most regions of China, human activities reduce water resources while climate change increases them. Southeastern China is the most influenced area, and its water resources decreased approximately 50 mm because of human activities. This study can provide a basis for water resource management under climate change and human activity constraints in China. [ABSTRACT FROM AUTHOR]