Simulating the spatiotemporal variations in aboveground biomass in Inner Mongolian grasslands under environmental changes

Abstract. Grassland aboveground biomass (AGB) is a critical component of the global carbon cycle and reflects ecosystem productivity. Although it is widely acknowledged that dynamics of grassland biomass is significantly regulated by climate change, in situ evidence at meaningfully large spatiotemporal scales is limited. Here, we combine biomass measurements from six long-term (> 30 years) experiments and data in existing literatures to explore the spatiotemporal changes in AGB in Inner Mongolian temperate grasslands. We show that, on average, annual AGB over the past 4 decades is 2561, 1496 and 835 kg ha−1, respectively, in meadow steppe, typical steppe and desert steppe in Inner Mongolia. The spatiotemporal changes of AGB are regulated by interactions of climatic attributes, edaphic properties, grassland type and livestock. Using a machine-learning-based approach, we map annual AGB (from 1981 to 2100) across the Inner Mongolian grasslands at the spatial resolution of 1 km. We find that on the regional scale, meadow steppe has the highest annual AGB, followed by typical and desert steppe. Future climate change characterized mainly by warming could lead to a general decrease in grassland AGB. Under climate change, on average, compared with the historical AGB (i.e. average of 1981–2019), the AGB at the end of this century (i.e. average of 2080–2100) would decrease by 14 % under Representative Concentration Pathway (RCP) 4.5 and 28 % under RCP8.5. If the carbon dioxide (CO2) enrichment effect on AGB is considered, however, the estimated decreases in future AGB can be reversed due to the growing atmospheric CO2 concentrations under both RCP4.5 and RCP8.5. The projected changes in AGB show large spatial and temporal disparities across different grassland types and RCP scenarios. Our study demonstrates the accuracy of predictions in AGB using a modelling approach driven by several readily obtainable environmental variables and provides new data at a large scale and fine resolution extrapolated from field measurements.

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Aboveground biomass in Inner Mongolian temperate grasslands decreases under climate warming

10.5194/acp-2020-1088 ◽

2020 ◽

Author(s):

Guocheng Wang ◽

Zhongkui Luo ◽

Yao Huang ◽

Wenjuan Sun ◽

Yurong Wei ◽

...

Keyword(s):

Climate Change ◽

Machine Learning ◽

Climate Warming ◽

Aboveground Biomass ◽

Future Climate ◽

Future Climate Change ◽

Desert Steppe ◽

Meadow Steppe ◽

Temperate Grasslands ◽

Spatiotemporal Changes

Abstract. Grassland aboveground biomass (AGB) is a critical component of the global carbon cycle and reflects ecosystem productivity. Although it is widely acknowledged that dynamics of grassland biomass are significantly regulated by climate change, in situ evidence at large spatiotemporal scales is limited. Here, we combine biomass measurements from six long-term (> 30 years) experiments and data in existing literatures to explore the spatiotemporal changes in AGB in Inner Mongolian temperate grasslands. We show that, on average, annual AGB over the past four decades is 2,561 ka ha−1, 1,496 kg ha−1 and 835 kg ha−1, respectively, in meadow steppe, typical steppe and desert steppe in Inner Mongolia. The spatiotemporal changes of AGB are regulated by interactions of climatic attributes, edaphic properties, grazing intensity and grassland type. Using a machine learning-based approach, we map annual AGB (from 1981 to 2100) across the Inner Mongolian grassland at the spatial resolution of 1 km. We find that on the regional scale, meadow steppe has the highest annual AGB, followed by typical and desert steppe. During 1981–2019, the average annual AGB generally exhibited a declining trend across all the three types of grassland. Under future climate warming, AGB in the study region could continue to decrease. On average, compared with the historical AGB (i.e., average of 1981–2019), the AGB at the end of this century (i.e., average of 2080–2100) would decrease by 14 % under RCP4.5 and 28 % under RCP8.5, respectively. The decreases in AGB under warming show large disparities across different grassland types and future climate change scenarios. Our results demonstrate the accuracy of predictions in AGB using a machine learning-based approach driven by several readily obtainable environmental variables; and provide new data at large scale and fine resolution extrapolated from field measurements.

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Large scale integrated hydrological modelling of the impact of climate change on the water balance with DANUBIA

Advances in Science and Research ◽

10.5194/asr-7-61-2011 ◽

2011 ◽

Vol 7 (1) ◽

pp. 61-70 ◽

Cited By ~ 15

Author(s):

M. Prasch ◽

T. Marke ◽

U. Strasser ◽

W. Mauser

Keyword(s):

Climate Change ◽

Time Series ◽

Water Balance ◽

Large Scale ◽

Regional Scale ◽

Future Climate ◽

Future Climate Change ◽

Impact Of Climate Change ◽

Ipcc Sres ◽

The Impact

Abstract. Future climate change will affect the water availability in large areas. In order to derive appropriate adaptation strategies the impact on the water balance has to be determined on a regional scale in a high spatial and temporal resolution. Within the framework of the BRAHMATWINN project the model system DANUBIA, developed within the project GLOWA Danube (GLOWA Danube, 2010; Mauser and Ludwig, 2002), was applied to calculate the water balance components under past and future climate conditions in the large-scale mountain watersheds of the Upper Danube and the Upper Brahmaputra. To use CLM model output data as meteorological drivers DANUBIA is coupled with the scaling tool SCALMET (Marke, 2008). For the determination of the impact of glacier melt water on the water balance the model SURGES (Weber et al., 2008; Prasch, 2010) is integrated into DANUBIA. In this paper we introduce the hydrological model DANUBIA with the tools SCALMET and SURGES. By means of the distributed hydrological time series for the past from 1971 to 2000 the model performance is presented. In order to determine the impact of climate change on the water balance in both catchments, time series from 2011 to 2080 according to the IPCC SRES emission scenarios A2, A1B, B2 and Commitment are analysed. Together with the socioeconomic outcomes (see Chapter 4) the DANUBIA model results provide the basis for the derivation of Integrated Water Resources Management Strategies to adapt to climate change impacts (see Chapter 9 and 10).

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Assessing the Vulnerability of Marine Fisheries in China: Towards an Inter-Provincial Perspective

Sustainability ◽

10.3390/su10114302 ◽

2018 ◽

Vol 10 (11) ◽

pp. 4302 ◽

Cited By ~ 1

Author(s):

Qi Chen ◽

Weiteng Shen ◽

Bing Yu

Keyword(s):

Climate Change ◽

Adaptive Capacity ◽

Fisheries Management ◽

Vocational Training ◽

Large Scale ◽

Environmental Changes ◽

Marine Pollution ◽

Marine Fisheries ◽

Intergovernmental Panel ◽

Adaptation Measures

China’s marine fisheries are undergoing large-scale environmental changes associated with climate change, marine pollution, and overfishing. The assessment of marine fisheries vulnerability has become extremely necessary for fisheries management and sustainable development. However, studies on China’s marine fisheries vulnerability remains sparse. This study aimed to provide an analysis of the inter-provincial level vulnerability of China’s marine fisheries under multiple disturbances. The vulnerability measure was composed of exposure, sensitivity, and adaptive capacity indicators specific to marine fisheries based on the Intergovernmental Panel on Climate Change (IPCC) definitions. Results showed that Liaoning, Hebei, Fujian, and Hainan provinces appeared to be the most vulnerable; Shanghai appeared to be less vulnerable among China’s 11 coastal provinces; and the key sources of vulnerability differed considerably among coastal regions. The high vulnerability regions could be divided into two different patterns according to the combination of exposure, sensitivity, and adaptive capacity, but they all had one thing in common: relatively low adaptive capacity. While some existing coercive measures to reduce dependence on fisheries were found to be helpful in China, the reality showed that appropriate adaptation measures such as improving fishermen’s education level and increasing vocational training may be helpful in enhancing the existing policy effectiveness.

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Current and future occurrences of health-relevant, compound heat and ozone pollution events in six European ozone-temperature regions

10.5194/ems2021-61 ◽

2021 ◽

Author(s):

Sally Jahn ◽

Elke Hertig

Keyword(s):

Climate Change ◽

Air Temperature ◽

Large Scale ◽

Coupled Model ◽

Ground Level ◽

Future Climate Change ◽

Ozone Pollution ◽

Ground Level Ozone ◽

Ozone Concentrations ◽

Elevated Ozone

Air pollution and heat events present two major health risks, both already independently posing a significant threat to human health and life. High levels of ground-level ozone (O3) and air temperature often coincide due to the underlying physical relationships between both variables. The most severe health outcome is in general associated with the co-occurrence of both hazards (e.g. Hertig et al. 2020), since concurrent elevated levels of temperature and ozone concentrations represent a twofold exposure and can lead to a risk beyond the sum of the individual effects. Consequently, in the current contribution, a compound approach considering both hazards simultaneously as so-called ozone-temperature (o-t-)events is chosen by jointly analyzing elevated ground-level ozone concentrations and air temperature levels in Europe.Previous studies already point to the fact that the relationship of underlying synoptic and meteorological drivers with one or both of these health stressors as well as the correlation between both variables vary with the location of sites and seasons (e.g. Otero et al. 2016; Jahn, Hertig 2020). Therefore, a hierarchical clustering analysis is applied to objectively divide the study domain in regions of homogeneous, similar ground-level ozone and temperature characteristics (o-t-regions). Statistical models to assess the synoptic and large-scale meteorological mechanisms which represent main drivers of concurrent o-t-events are developed for each identified o-t-region.Compound elevated ozone concentration and air temperature events are expected to become more frequent due to climate change in many parts of Europe (e.g. Jahn, Hertig 2020; Hertig 2020). Statistical projections of potential frequency shifts of compound o-t-events until the end of the twenty-first century are assessed using the output of Earth System Models (ESMs) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6).Hertig, E. (2020) Health-relevant ground-level ozone and temperature events under future climate change using the example of Bavaria, Southern Germany. Air Qual. Atmos. Health. doi: 10.1007/s11869-020-00811-zHertig, E., Russo, A., Trigo, R. (2020) Heat and ozone pollution waves in Central and South Europe- characteristics, weather types, and association with mortality. Atmosphere. doi: 10.3390/atmos11121271Jahn, S., Hertig, E. (2020) Modeling and projecting health&#8208;relevant combined ozone and temperature events in present and future Central European climate. Air Qual. Atmos. Health. doi: 10.1007/s11869&#8208;020&#8208;009610Otero N., Sillmann J., Schnell J.L., Rust H.W., Butler T. (2016) Synoptic and meteorological drivers of extreme ozone concentrations over Europe. Environ Res Lett. doi: 10.1088/ 1748-9326/11/2/024005

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Impact of climate change on groundwater point discharge: backflooding of karstic springs (Loiret, France)

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-2235-2011 ◽

2011 ◽

Vol 8 (2) ◽

pp. 2235-2262

Author(s):

E. Joigneaux ◽

P. Albéric ◽

H. Pauwels ◽

C. Pagé ◽

L. Terray ◽

...

Keyword(s):

Climate Change ◽

Surface Water ◽

Groundwater Quality ◽

Atmospheric Circulation ◽

Large Scale ◽

Weather Type ◽

Future Climate Change ◽

Impact Of Climate Change ◽

The Impact ◽

Large Scale Atmospheric Circulation

Abstract. Under certain hydrological conditions it is possible for spring flow in karst systems to be reversed. When this occurs, the resulting invasion by surface water, i.e. the backflooding, represents a serious threat to groundwater quality because the surface water could well be contaminated. Here we examine the possible impact of future climate change on the occurrences of backflooding in a specific karst system, having first established the occurrence of such events in the selected study area over the past 40 yr. It would appear that backflooding has been more frequent since the 1980s, and that it is apparently linked to river flow variability on the pluri-annual scale. The avenue that we adopt here for studying recent and future variations of these events is based on a downscaling algorithm relating large-scale atmospheric circulation to local precipitation spatial patterns. The large-scale atmospheric circulation is viewed as a set of quasi-stationary and recurrent states, called weather types, and its variability as the transition between them. Based on a set of climate model projections, simulated changes in weather-type occurrence for the end of the century suggests that backflooding events can be expected to decrease in 2075–2099. If such is the case, then the potential risk for groundwater quality in the area will be greatly reduced compared to the current situation. Finally, our results also show the potential interest of the weather-type based downscaling approach for examining the impact of climate change on hydrological systems.

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Atmospheric Dynamics Feedback: Concept, Simulations, and Climate Implications

Journal of Climate ◽

10.1175/jcli-d-17-0470.1 ◽

2018 ◽

Vol 31 (8) ◽

pp. 3249-3264 ◽

Cited By ~ 9

Author(s):

Michael P. Byrne ◽

Tapio Schneider

Keyword(s):

Climate Change ◽

Atmospheric Circulation ◽

Radiative Forcing ◽

Large Scale ◽

Climate Models ◽

Atmospheric Dynamics ◽

Future Climate Change ◽

Coupled Models ◽

Near Surface ◽

Circulation Changes

AbstractThe regional climate response to radiative forcing is largely controlled by changes in the atmospheric circulation. It has been suggested that global climate sensitivity also depends on the circulation response, an effect called the “atmospheric dynamics feedback.” Using a technique to isolate the influence of changes in atmospheric circulation on top-of-the-atmosphere radiation, the authors calculate the atmospheric dynamics feedback in coupled climate models. Large-scale circulation changes contribute substantially to all-sky and cloud feedbacks in the tropics but are relatively less important at higher latitudes. Globally averaged, the atmospheric dynamics feedback is positive and amplifies the near-surface temperature response to climate change by an average of 8% in simulations with coupled models. A constraint related to the atmospheric mass budget results in the dynamics feedback being small on large scales relative to feedbacks associated with thermodynamic processes. Idealized-forcing simulations suggest that circulation changes at high latitudes are potentially more effective at influencing global temperature than circulation changes at low latitudes, and the implications for past and future climate change are discussed.

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Vulnerability of coastal areas to increased aquifer saturation due to climate change

10.5194/egusphere-egu21-14870 ◽

2021 ◽

Author(s):

Alexandre Gauvain ◽

Ronan Abhervé ◽

Jean-Raynald de Dreuzy ◽

Luc Aquilina ◽

Frédéric Gresselin

Keyword(s):

Climate Change ◽

Sea Level ◽

Large Scale ◽

Regional Scale ◽

Drainage System ◽

Hydrological Regime ◽

Coastal Areas ◽

Western Coast ◽

Study Sites ◽

The Impact

Like in other relatively flat coastal areas, flooding by aquifer overflow is a recurring problem on the western coast of Normandy (France). Threats are expected to be enhanced by the rise of the sea level and to have critical consequences on the future development and management of the territory. The delineation of the increased saturation areas is a required step to assess the impact of climate change locally. Preliminary models showed that vulnerability does not result only from the sea side but also from the continental side through the modifications of the hydrological regime.We investigate the processes controlling these coastal flooding phenomena by using hydrogeological models calibrated at large scale with an innovative method reproducing the hydrographic network. Reference study sites selected for their proven sensitivity to flooding have been used to validate the methodology and determine the influence of the different geomorphological configurations frequently encountered along the coastal line.Hydrogeological models show that the rise of the sea level induces an irregular increase in coastal aquifer saturations extending up to several kilometers inland. Back-littoral channels traditionally used as a large-scale drainage system against high tides limits the propagation of aquifer saturation upstream, provided that channels are not dominantly under maritime influence. High seepage fed by increased recharge occurring in climatic extremes may extend the vulnerable areas and further limit the effectiveness of the drainage system. Local configurations are investigated to categorize the influence of the local geological and geomorphological structures and upscale it at the regional scale.

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Considering adaptive genetic variation in climate change vulnerability assessment reduces species range loss projections

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1820663116 ◽

2019 ◽

Vol 116 (21) ◽

pp. 10418-10423 ◽

Cited By ~ 67

Author(s):

Orly Razgour ◽

Brenna Forester ◽

John B. Taggart ◽

Michaël Bekaert ◽

Javier Juste ◽

...

Keyword(s):

Climate Change ◽

Genetic Variation ◽

Environmental Changes ◽

Landscape Connectivity ◽

Future Climate ◽

Future Climate Change ◽

Adaptive Genetic Variation ◽

Climate Change Vulnerability ◽

Species Vulnerability ◽

Evolutionary Rescue

Local adaptations can determine the potential of populations to respond to environmental changes, yet adaptive genetic variation is commonly ignored in models forecasting species vulnerability and biogeographical shifts under future climate change. Here we integrate genomic and ecological modeling approaches to identify genetic adaptations associated with climate in two cryptic forest bats. We then incorporate this information directly into forecasts of range changes under future climate change and assessment of population persistence through the spread of climate-adaptive genetic variation (evolutionary rescue potential). Considering climate-adaptive potential reduced range loss projections, suggesting that failure to account for intraspecific variability can result in overestimation of future losses. On the other hand, range overlap between species was projected to increase, indicating that interspecific competition is likely to play an important role in limiting species’ future ranges. We show that although evolutionary rescue is possible, it depends on a population’s adaptive capacity and connectivity. Hence, we stress the importance of incorporating genomic data and landscape connectivity in climate change vulnerability assessments and conservation management.

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Understanding Future Water Challenges in a Highly Regulated Indian River Basin—Modelling the Impact of Climate Change on the Hydrology of the Upper Narmada

Water ◽

10.3390/w12061762 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1762 ◽

Cited By ~ 2

Author(s):

Nathan Rickards ◽

Thomas Thomas ◽

Alexandra Kaelin ◽

Helen Houghton-Carr ◽

Sharad K. Jain ◽

...

Keyword(s):

Climate Change ◽

Water Resources ◽

River Basin ◽

Large Scale ◽

Monsoon Season ◽

Future Climate Change ◽

Impact Of Climate Change ◽

Global Circulation Models ◽

The Impact ◽

Availability Assessment

The Narmada river basin is a highly regulated catchment in central India, supporting a population of over 16 million people. In such extensively modified hydrological systems, the influence of anthropogenic alterations is often underrepresented or excluded entirely by large-scale hydrological models. The Global Water Availability Assessment (GWAVA) model is applied to the Upper Narmada, with all major dams, water abstractions and irrigation command areas included, which allows for the development of a holistic methodology for the assessment of water resources in the basin. The model is driven with 17 Global Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) ensemble to assess the impact of climate change on water resources in the basin for the period 2031–2060. The study finds that the hydrological regime within the basin is likely to intensify over the next half-century as a result of future climate change, causing long-term increases in monsoon season flow across the Upper Narmada. Climate is expected to have little impact on dry season flows, in comparison to water demand intensification over the same period, which may lead to increased water stress in parts of the basin.

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A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2014.0423 ◽

2015 ◽

Vol 373 (2054) ◽

pp. 20140423 ◽

Cited By ~ 96

Author(s):

C. D. Koven ◽

E. A. G. Schuur ◽

C. Schädel ◽

T. J. Bohn ◽

E. J. Burke ◽

...

Keyword(s):

Climate Change ◽

Large Scale ◽

Climate Feedback ◽

Soil Horizon ◽

Future Climate Change ◽

Thermal Dynamics ◽

Soil C ◽

Warming Scenario ◽

C Stocks ◽

Permafrost Soils

We present an approach to estimate the feedback from large-scale thawing of permafrost soils using a simplified, data-constrained model that combines three elements: soil carbon (C) maps and profiles to identify the distribution and type of C in permafrost soils; incubation experiments to quantify the rates of C lost after thaw; and models of soil thermal dynamics in response to climate warming. We call the approach the Permafrost Carbon Network Incubation–Panarctic Thermal scaling approach (PInc-PanTher). The approach assumes that C stocks do not decompose at all when frozen, but once thawed follow set decomposition trajectories as a function of soil temperature. The trajectories are determined according to a three-pool decomposition model fitted to incubation data using parameters specific to soil horizon types. We calculate litterfall C inputs required to maintain steady-state C balance for the current climate, and hold those inputs constant. Soil temperatures are taken from the soil thermal modules of ecosystem model simulations forced by a common set of future climate change anomalies under two warming scenarios over the period 2010 to 2100. Under a medium warming scenario (RCP4.5), the approach projects permafrost soil C losses of 12.2–33.4 Pg C; under a high warming scenario (RCP8.5), the approach projects C losses of 27.9–112.6 Pg C. Projected C losses are roughly linearly proportional to global temperature changes across the two scenarios. These results indicate a global sensitivity of frozen soil C to climate change ( γ sensitivity) of −14 to −19 Pg C °C −1 on a 100 year time scale. For CH 4 emissions, our approach assumes a fixed saturated area and that increases in CH 4 emissions are related to increased heterotrophic respiration in anoxic soil, yielding CH 4 emission increases of 7% and 35% for the RCP4.5 and RCP8.5 scenarios, respectively, which add an additional greenhouse gas forcing of approximately 10–18%. The simplified approach presented here neglects many important processes that may amplify or mitigate C release from permafrost soils, but serves as a data-constrained estimate on the forced, large-scale permafrost C response to warming.

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