Asia's high plateaus are sensitive to climate change and have been experiencing rapid warming over the past few decades. We found 99 new lakes and extensive lake expansion on the Tibetan Plateau ...during the last four decades, 1970–2013, due to increased precipitation and cryospheric contributions to its water balance. This contrasts with disappearing lakes and drastic shrinkage of lake areas on the adjacent Mongolian Plateau: 208 lakes disappeared, and 75% of the remaining lakes have shrunk. We detected a statistically significant coincidental timing of lake area changes in both plateaus, associated with the climate regime shift that occurred during 1997/1998. This distinct change in 1997/1998 is thought to be driven by large‐scale atmospheric circulation changes in response to climate warming. Our findings reveal that these two adjacent plateaus have been changing in opposite directions in response to climate change. These findings shed light on the complex role of the regional climate and water cycles and provide useful information for ecological and water resource planning in these fragile landscapes.
Key Points
Contrasting patterns of lake change between the Mongolian Plateau (MP) and Tibetan Plateau (TP)
A clear inflection point of lake change during 1997/1998 on both plateaus
The warmer‐drier climate in MP, contrasting the warmer‐wetter climate in TP, has driven drastically different patterns of lake evolutions
Abstract Management practices that increase the surface albedo of cultivated land could mitigate climate change, with similar effectiveness to practices that reduce greenhouse gas emissions or favor ...natural CO2 sequestration. Yet, the efficiency of such practices is barely quantified. In this study, we quantified the impacts of seven different management practices on the surface albedo of winter wheat fields (nitrogen fertilizer, herbicide, fungicide, sowing, harvest, tillage, and crop residues) by analyzing observed daily albedo dynamics from eight European flux-tower sites with interpretable machine learning. We found that management practices have significant influences on surface albedo dynamics compared with climate and soil conditions. The nitrogen fertilizer application has the largest effect among the seven practices as it increases surface albedo by 0.015±0.004 during the first two months after application, corresponding to a radiative forcing of -4.39±1.22 W m−2. Herbicide induces a modest albedo decrease of 0.005±0.002 over 150 days after application by killing weeds in the fallow period only, resulting in a magnitude of radiative forcing of 1.33±1.06 W m−2 which is higher than radiative forcing of other practices in the same period. The substantial temporal evolution of the albedo impacts of management practices increases uncertainties in the estimated albedo-mediated climate impacts of management practices. Although these albedo effects are smaller than published estimates of the greenhouse gas-mediated biogeochemical practices, they are nevertheless significant and should thus be accounted for in climate impact assessments.
Knowledge of the contribution that individual countries have made to global radiative forcing is important to the implementation of the agreement on "common but differentiated responsibilities" ...reached by the United Nations Framework Convention on Climate Change. Over the past three decades, China has experienced rapid economic development, accompanied by increased emission of greenhouse gases, ozone precursors and aerosols, but the magnitude of the associated radiative forcing has remained unclear. Here we use a global coupled biogeochemistry-climate model and a chemistry and transport model to quantify China's present-day contribution to global radiative forcing due to well-mixed greenhouse gases, short-lived atmospheric climate forcers and land-use-induced regional surface albedo changes. We find that China contributes 10% ± 4% of the current global radiative forcing. China's relative contribution to the positive (warming) component of global radiative forcing, mainly induced by well-mixed greenhouse gases and black carbon aerosols, is 12% ± 2%. Its relative contribution to the negative (cooling) component is 15% ± 6%, dominated by the effect of sulfate and nitrate aerosols. China's strongest contributions are 0.16 ± 0.02 watts per square metre for CO2 from fossil fuel burning, 0.13 ± 0.05 watts per square metre for CH4, -0.11 ± 0.05 watts per square metre for sulfate aerosols, and 0.09 ± 0.06 watts per square metre for black carbon aerosols. China's eventual goal of improving air quality will result in changes in radiative forcing in the coming years: a reduction of sulfur dioxide emissions would drive a faster future warming, unless offset by larger reductions of radiative forcing from well-mixed greenhouse gases and black carbon.
This open access book introduces the function, implementation and governance of green infrastructure in Japan and other countries where lands are geologically fragile and climatologically susceptible ...to climate change. It proposes green infrastructure as an adaptation strategy for climate change and biodiversity conservation. In the face of climate change, dams, levees and floodways built as disaster prevention facilities do not sufficiently function against extraordinary events such as mega-floods and tsunami disasters. To prevent those disasters and loss of biodiversity in various ecosystems, we should shift from conventional hard measures to more adaptive strategies using various functions that natural and semi-natural ecosystems provide. Green infrastructure is an interconnected network of waterways, wetlands, woodlands, wildlife habitats and other natural areas that support native species, maintain natural ecological processes, sustain air and water resources and contribute to the health and quality of life for communities and people. Green infrastructure has mainly been discussed from adaptation strategy perspectives in cities and urban areas. However, to protect cities, which are generally situated at downstream lower elevations, we explore the preservation and restoration of forests at headwater basins and wetlands along rivers from a catchment perspective. In addition, the quantitative examination of flood risk, biodiversity, and social-economic benefits described in this book brings new perspectives to the discussion. The aim of this book is to accelerate the transformative changes from gray-based adaptation strategies to green- or hybrid-based strategies to adapt to climate change. The book provides essential information on the structure, function, and maintenance of green infrastructure for scientists, university students, government officers, and practitioners.
Climate warming would increase the active layer thickness (ALT) of permafrost, which can cause changes in the hydrological cycle, ecological processes, and carbon flux in cold regions. However, ...changes in permafrost ALT due to climate warming remain poorly quantified, which limits our understanding of environmental change in cold regions. In this study, the Lund‐Postam‐Jena dynamic vegetation model is coupled to the Kudryavtsev model to examine changes in permafrost ALT on the Qinghai‐Tibet Plateau (QTP) under climate change scenarios based on the representative concentration pathways (RCPs). The results suggest that the permafrost ALT on the QTP would exhibit a significant increasing trend under the climate change scenarios, and a large increment of ALT may occur in the northwestern QTP. In the near‐term (2011–2040), the change in ALT on the QTP is different under the RCP2.6, RCP4.5, RCP6.0, and RCP8.5 emissions scenarios, with an increment of 5–30 cm. In the mid‐term (2041–2070), ALT would deepen further with an obvious reduction in permafrost area, while the increase in ALT decreases from south to north. In the long‐term (2071–2099), the average increment of ALT would be greater than 30 cm under the RCP4.5, RCP6.0, and RCP8.5 scenarios, and the increment in ALT increases from south to north, with a remarkable retreat in permafrost area from south to north.
Key Points
Climate change negatively affected the active layer thickness of permafrost on the Qinghai‐Tibet Plateau
Increment of active layer thickness shows a rising trend from the south to the north
Permafrost area would retreat toward the interior of Qinghai‐Tibet Plateau with active layer thickness enhancement
Forest vulnerability to drought is expected to increase under anthropogenic climate change, and drought-induced mortality and community dynamics following drought have major ecological and societal ...impacts. Here,we showthat tree mortality concomitant with drought has led to short-term (mean 5 y, range 1 to 23 y after mortality) vegetation-type conversion in multiple biomes across the world (131 sites). Self-replacement of the dominant tree species was only prevalent in 21% of the examined cases and forests and woodlands shifted to nonwoody vegetation in 10% of them. The ultimate temporal persistence of such changes remains unknown but, given the key role of biological legacies in long-term ecological succession, this emerging picture of postdrought ecological trajectories highlights the potential for major ecosystem reorganization in the coming decades. Community changes were less pronounced under wetter postmortality conditions. Replacement was also influenced by management intensity, and postdrought shrub dominance was higher when pathogens acted as codrivers of tree mortality. Early change in community composition indicates that forests dominated by mesic species generally shifted toward more xeric communities, with replacing tree and shrub species exhibiting drier bioclimatic optima and distribution ranges. However, shifts toward more mesic communities also occurred and multiple pathways of forest replacement were observed for some species. Drought characteristics, species-specific environmental preferences, plant traits, and ecosystem legacies govern postdrought species turnover and subsequent ecological trajectories, with potential far-reaching implications for forest biodiversity and ecosystem services.
We calculate ozone radiative forcing (RF) and stratospheric temperature adjustments for the period 1850–2014 using the newly available Coupled Model Intercomparison Project phase 6 (CMIP6) ozone data ...set. The CMIP6 total ozone RF (1850s to 2000s) is 0.28 ± 0.17 W m−2 (which is 80% higher than our CMIP5 estimation), and 0.30 ± 0.17 W m−2 out to the present day (2014). The total ozone RF grows rapidly until the 1970s, slows toward the 2000s, and shows a renewed growth thereafter. Since the 1990s the shortwave RF exceeds the longwave RF. Global stratospheric ozone RF is positive between 1930 and 1970 and then turns negative but remains positive in the Northern Hemisphere throughout. Derived stratospheric temperature changes show a localized cooling in the subtropical lower stratosphere due to tropospheric ozone increases and cooling in the upper stratosphere due to ozone depletion by more than 1 K already prior to the satellite era (1980) and by more than 2 K out to the present day (2014).
Plain Language Summary
Radiative forcing is a key concept used in climate science to ascertain the strength of different agents, such as greenhouse gases or aerosols among others, in driving climate change. In this context, ozone is recognized as one of the main contributors to radiative forcing according to recent assessments of the Intergovernmental Panel on Climate Change. However, the relative uncertainty remains higher than for other greenhouse gases. This paper evaluates the ozone radiative forcing via calculations based on a newly created ozone data set for the Coupled Model Intercomparison Project (CMIP) phase 6, an initiative designed to better understand past, present, and future climate changes. In general, human activity has led to an increase in ozone concentrations in the lower atmosphere (the troposphere) and decreases in the upper atmosphere (the stratosphere); our paper investigates the effect of both these changes. Our results indicate that the CMIP ozone radiative forcing is 80% larger in the current phase 6 than a similar estimation based on data used in CMIP phase 5. We also present new insights into how ozone changes have led to stratospheric temperature changes, as well as the geographical distribution of ozone radiative forcing.
Key Points
The 1850‐2010 ozone radiative forcing for the CMIP6 ozone database is 80% higher than for CMIP5
The long‐term stratospheric ozone radiative forcing in the Northern Hemisphere is positive despite recent ozone depletion
Tropospheric and stratospheric ozone changes both lead to long‐term marked cooling patterns in the stratosphere
The pace of energy use, greenhouse gas emissions, and population growth has thrust the planet into a new age--the Anthropocene. Humans have altered the planet's biogeochemical systems without ...consciously managing them. The Great Acceleration explains the causes, consequences, and uncertainties of this massive uncontrolled experiment.
Climate change is a lived experience of changes in the environment, often destroying conventional forms of subsistence and production, creating new patterns of movement and connection, and ...transforming people's imagined future.
This book explores how people across the world think about environmental change and how they act upon the perception of past, present and future opportunities. Drawing on the ethnographic fieldwork of expert authors, it sheds new light on the human experience of and social response to climate change by taking us from the Arctic to the Pacific, from the Southeast Indian Coastal zone to the West-African dry-lands and deserts, as well as to Peruvian mountain communities and cities.
Divided into four thematic parts - Water, Landscape, Technology, Time - this book uses rich photographic material to accompany the short texts and reflections in order to bring to life the human ingenuity and social responsibility of people in the face of new uncertainties. In an era of melting glaciers, drying lands, and rising seas, it shows how it is part and parcel of human life to take responsibility for the social community and take creative action on the basis of a localized understanding of the environment.
This highly original contribution to the anthropological study of climate change is a must-read for all those wanting to understand better what climate change means on the ground and interested in a sustainable future for the Earth.
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