Meltwater Research Articles

Subsurface evolution of the seasonally frozen ground on the northeastern Tibetan Plateau from a perspective of seismic interferometry

Summary The Tibetan Plateau, a critical region influencing both local and global atmospheric circulation, climate dynamics, hydrology, and terrestrial ecosystems, is undergoing climate-driven changes, including glacial retreat, permafrost thaw, and groundwater changes. Despite its importance, implementing continuous and systematic observations have been challenging due to the area’s high altitude and extreme climate conditions. In this context, seismic interferometry emerges as a cost-effective method for the continuous monitoring of subsurface structural changes driven by environmental factors and internal geophysical processes. We investigate subsurface evolution using four years of seismic data from nine stations on the northeastern Tibetan Plateau, by applying coda wave interferometry across multiple frequency bands. Our findings highlight seismic velocity changes within the frequency bands 5–10 Hz, 0.77–1.54 Hz, and 0.25–0.51 Hz, revealing depth-dependent seasonal and long-term changes. Near-surface and deeper strata exhibit similar seasonal patterns, with velocities increasing in winter and decreasing in summer driven by changes in hydrological processes, while intermediate ice-water phase strata show contrasting behavior due to thermal elastic strain. Long-term trends suggest that the upper subsurface layer is affected by melting water and precipitation originating from Kunlun Mountains, whereas deeper layer reflect groundwater level variations influenced by climate change and human activities. This study provides insights into the environmental evolution of the Tibetan Plateau and its impact on managing local groundwater resources.

Assessing climate sensitivity of the Upper Indus Basin using fully distributed, physically-based hydrologic modeling and multi-model climate ensemble approach

The Upper Indus Basin (UIB) of Pakistan is home to three largest mountain ranges: Karakoram, Hindukush, and the Himalayas. There’s a hovering danger of reduced water resources due to climate-induced warming, since the Indus Basin relies mostly on snow and glacier melt runoff from these mountains. In this study, the hydrology of these areas is studied to estimate variability in water resources under changing climate. A coupled hydrologic/hydraulic model, MIKE SHE/MIKE HYDRO RIVER, was used to calibrate and validate the model using streamflow data at the Shatial gauge station. The bias-corrected multi-model ensemble dataset accessed from the coordinated regional climate downscaling experiment (CORDEX) for two scenarios RCP 4.5 and RCP 8.5 were used up to the end of twenty-first century for the projection of stream flow. The calibrated model depicts an increase of 86% for RCP4.5 and 97% for RCP8.5, dominated by increased snow melt contribution due to consistent warming trends (average increase of 2.3 and 4 °C, annually for RCP 4.5 and 8.5, respectively). The most prominent increase was observed in winter months when predicted flows increased by 300% from historic. With predicted annual average available water of 4500 m3/s under RCP8.5, the study concludes that the available water would relieve some of the water stress in the country. However, the increased availability of water can also cause catastrophic floods. More flood defense and storage structures are needed to improve management practices in the downstream areas, particularly during wet and dry years.

Assessment of runoff generation capacity and total runoff contribution for different landscapes in alpine and permafrost watershed

Alpine vegetation, cold deserts, and glacial landscapes significantly impact runoff generation and convergence in cold and alpine regions. The presence of existing mountain permafrost complicates these impacts further. To better understand the specific regulation of runoff by alpine landscapes, we analyzed the spatiotemporal capacity for runoff generation and the contributions of water from different landscape types within a typical alpine permafrost watershed: the upper reaches of the Shule River (USR) basin in the Qinghai-Tibet Plateau. The analysis was informed by both field observations and simulations using the VIC model, which incorporated a new glacier module. We identified that glaciers, alpine meadows, cold deserts, and barren landscape zones as the four major runoff generation regions, collectively accounting for approximately 95 % of the USR runoff. The runoff depth in each landscape zone was calculated to express its “runoff generation capacity,” with an order of: glacier > cold desert > barren > alpine grassland > alpine meadow > shrub > swamp meadow. The alpine regions above 4000 m in altitude are the primary runoff generation areas, and the “runoff generation capacity” gradually decreases from high to low altitudes in the alpine basin. Due to seasonal variations in rainfall distribution, glacier melting, and permafrost thawing-freezing, the dominant landscape types contributing to runoff varied monthly. The simulated results indicate that permafrost plays an important role in runoff generation. Although permafrost degradation had a slight impact on the annual total runoff generated from each landscape zone (not taking into account of ground ice), seasonal runoff generated in each landscape exhibited significant changes in response to permafrost thawing. After permafrost completely thawed in each landscape zone, generated flood flow decreased, while low flow conversely increased, implying an enhanced water retention capacity of alpine landscapes following permafrost degradation. Additionally, the responses of runoff to permafrost changes varied across different alpine landscapes. These findings enhance our understanding of the mechanisms underlying runoff generation and convergence in cold and alpine watersheds of the Northern Hemisphere.

Mitigating ice sheets and mountain glaciers melt with geoengineering.

The inadequacy of current emission reduction measures necessitates exploring innovative approaches to address the critical issue of ice sheet and mountain glacier melting. Geoengineering emerges as a potential solution to mitigate severe cryospheric changes. This review systematically examines geoengineering techniques tailored to ice sheets and mountain glaciers, analyzing their efficacy, risks, and limitations based on existing literature. Results indicate that while geoengineering technologies can reduce glacier and ice sheet melting, challenges related to environmental risks, ethical dilemmas, and technical feasibility constrain their broader application. Probably more important than technical feasibility is societal acceptance. Therefore, their application raises critical ethical questions, including intergenerational responsibility and equitable resource allocation. Ultimately, the review proposed seven recommendations: focusing on energy conservation and emissions reduction; integrating technologies and strategies; developing means to optimize albedo enhancement; implementing dynamic monitoring; comprehensively assessing the socio-ecological and economic benefits and risks of technologies; transnational climate governance and cooperation; and building ethical and legal frameworks. These strategies aim to guide policymakers in developing effective and equitable strategies for mitigating ice sheet and mountain glacier melting in the context of global climate change.

Deep learning model based prediction of vehicle CO2 emissions with eXplainable AI integration for sustainable environment

The transportation industry contributes significantly to climate change through carbon dioxide (CO2) emissions, intensifying global warming and leading to more frequent and severe weather phenomena such as flooding, drought, heat waves, glacier melting, and rising sea levels. This study proposes a comprehensive approach for predicting CO2 emissions from vehicles using deep learning techniques enhanced by eXplainable Artificial Intelligence (XAI) methods. Utilizing a dataset from the Canadian government’s official open data portal, we explored the impact of various vehicle attributes on CO2 emissions. Our analysis reveals that not only do high-performance engines emit more pollutants, but fuel consumption under both city and highway conditions also contributes significantly to higher emissions. We identified skewed distributions in the number of vehicles produced by different manufacturers and trends in fuel consumption across fuel types. This study used deep learning techniques to construct a CO2 emission prediction model, specifically a light multilayer perceptron (MLP) architecture called CarbonMLP. The proposed model was optimized by hyperparameter tuning and achieved excellent performance metrics, such as a high R-squared value of 0.9938 and a low Mean Squared Error (MSE) of 0.0002. This study employs XAI approaches, particularly SHapley Additive exPlanations (SHAP), to improve the model interpretation ability and provide information about the importance of features. The findings of this study show that the proposed methodology accurately predicts CO2 emissions from vehicles. Additionally, the analysis suggests areas for further research, such as increasing the dataset, integrating additional pollutants, improving interpretability, and investigating real-world applications. Overall, this study contributes to the design of effective strategies for reducing vehicle CO2 emissions and promoting environmental sustainability.

Vegetation Fire Emissions Exacerbate Glacier Melting on the Third Pole.

Vegetation fires release a large fraction of light-absorbing components, which can contribute to the melting of snowpack and alpine glaciers. However, the relationship between variability in fire emissions and alpine glacier melting on the Third Pole (TP) remains poorly understood. This study provides evidence that carbon emissions from windward vegetation fires play a crucial role in comprehending glacier melting on the TP, particularly during the months of intense vegetation fires from March to May for monsoon-dominated glaciers and from June to October for westerlies-dominated glaciers. Furthermore, robust positive correlations (with p < 0.05) have been observed since 1997 across the TP between variations in glacier melting and fire carbon emissions during both annual periods and those intense fire months. In addition to climate warming, intensified fire carbon emissions could potentially accelerate the melting and mass loss of TP glaciers, especially during those traditionally nonmelting months. An urgent reassessment of the impact of fire carbon emissions on changes in TP glaciers is necessary, given that meltwater during traditionally nonmelting months can reshape freshwater resource supply patterns, and the projected increased wildfire risk in high mountainous regions in a rapidly warming climate.

Understanding the atmospheric dynamics over high-altitude glaciated regions in the central Himalaya using high-resolution numerical simulations

Abstract The atmospheric dynamics over the higher Himalaya play a crucial role in controlling glacier variability and ultimately regulating downstream water availability. However, the paucity of station observations makes exploring these atmospheric dynamics challenging. To address these issues, we employed a high-resolution configuration of the Weather Research and Forecasting (WRF) model with a 2-km convection-permitting grid scale to simulate atmospheric variables over the central Himalaya. We analyze the atmospheric variables over three high-altitude glaciated regions, namely the Langtang, Rolwaling, and Everest regions, in the central Himalaya. The model reproduces precipitation and temperature seasonality well, with the model precipitation displaying better agreement with the station data and outperforming the satellite observations. Furthermore, we investigate the spatial variability of precipitation during the monsoon and winter seasons and explore the associated dynamics by computing the vertically integrated moisture transport (VIMT) and vertically integrated moisture flux divergence (VIMFD). The VIMT and VIMFD analysis reveal that the valleys that meridionally dissect the Himalaya transport the moisture from the Indo-Gangetic plains to the higher Himalaya, and the sharp rise in elevation results in moisture convergence and precipitation, with the results that the ridges and windward slopes accumulate more precipitation than the leeward slopes and valleys. The orographic effect on moisture convergence, cloud formation, and precipitation consequently controls the glacier energy balance. During the monsoon season, the enhancement of net radiation by thick monsoon cloud cover, coupled with added latent heat and reduced albedo from the dominant liquid precipitation below 5,000 m amsl, increases the melt energy, promoting glacier melt.

Understanding Marine Biodiversity Shifts in Southeast Greenland with Indigenous and Local Knowledge

Abstract We contribute to the identification of marine biodiversity status and changes in the coastal area of Southeast Greenland through consultation with holders of local and Indigenous knowledge (LEK/IK). Through in-depth interviews with coastal fishers and hunters in the Ammassalik area, we explore a range of changes to known and new species in relation to ecosystem dynamics. Key observations include diminishing presence of polar cod (Boreogadus saida), new abundance of known fish species (Gadus morhua, Salvelinus alpinus, Reinhardtius hippoglossoides, Cyclopterus lumpus), inflow of new/rare species of whales, fish, and shellfish (Oncorhynchus gorbuscha, Lamna nasus, Paralithodes camtschaticus, Physeter macrocephalus, Globicephala melas, Megaptera novaeangliae, Phocoena phocoena), and increasing absence in the fjords of some local seal species (Cystophora cristata and Pusa hispida). Observed changes in local abundances are understood with reference to the physical changes in temperature, ocean currents, glacier melt, and snowfall. Changed dynamics in prey-predator relationships are observed to mediate the local presence of target species. Other environmental changes include an influx of new food items in food chains and increased seaweed growth. Our study confirms the relevance and timeliness of systematically incorporating local and Indigenous knowledge to enhance the understanding of coastal marine dynamics in the context of climate change and the geographical ‘opening’ of the East Greenlandic region.

In Situ Characterization of Dust Storms and Their Snow‐Darkening Effect Over Himalayas

AbstractIn this study, we used satellite observations to identify 10 typical dust‐loading events over the Indian Himalayas. Next, the aerosol microphysical and optical properties during these identified dust storms are characterized using cotemporal in situ measurements over Mukteshwar, a representative site in Indian Himalayas. Relative to the background values, the mass of coarse particles (size range between 2.5 and 10 μm) and the extinction coefficient were found to be enhanced by 400% (from 24 ± 15 to 98 ± 40 μg/m3) and 175% (from 89 ± 57 Mm−1 to 156 ± 79 Mm−1), respectively, during these premonsoonal dust‐loading events. Moreover, based on the air mass trajectory, these dust storms can be categorized into two categories: (a) mineral dust events (MDEs), which involve long‐range transported dust plumes traversing through the lower troposphere to reach the Himalayas and (b) polluted dust events (PDEs), which involve short‐range transported dust plumes originating from the arid western regions of the Indian subcontinent and traveling within the heavily polluted boundary layer of the Gangetic plains before reaching the Himalayas. Interestingly, compared to the background, the SSA and AAE decrease during PDEs but increase during MDEs. More importantly, we observe a twofold increase in black carbon concentrations and the aerosol absorption coefficient (relative to the background values) during the PDEs with negligible changes during MDEs. Consequently, the aerosol‐induced snow albedo reduction (SAR) also doubles during MDEs and PDEs relative to background conditions. Thus, our findings provide robust observational evidence of substantial dust‐induced snow and glacier melting over the Himalayas.

Hydrochemical Dynamics of River Flow in a Mountain River (Katun River as an Example)

It is noted that the efficiency of protection and rational use of water resources decreases due to uncertainty of information about spontaneously changing indicators of their quality, uniqueness of such variability and, consequently, due to impossibility to develop uniform rules of economic use of water bodies and watercourses. It is shown that these problems arise not only in water bodies subjected to intensive anthropogenic impact, but also in those remaining in practically natural conditions. The results of the authors' studies of the rivers of the Altai Mountains are presented, where such features of melt (freshly formed) water as structural shifts in time series of its quality indicators, clustering of volatility, non-seasonal cyclicity and long memory of time series were discovered. It was concluded that it is necessary to take into account not only external conditions but also intrinsic dynamic characteristics of water flow to assess water composition and properties in order to reliably predict its quality and ensure efficient water use.

Modeling the Impact of Greenland Ice Sheet Melting on Global Sea Level Elevation and Climate Change Feedback Mechanisms

The rapid acceleration of global warming is leading to an increased rate of glacier melt at the Earth's poles, which exacerbates the threats posed by the climate crisis and contributes to rising ocean levels. The Greenland Ice Sheet, recognized as the second-largest ice sheet globally, has housed its extensive glaciers and ice caps for at least 18 million years [1]. The melting and potential collapse of this ice sheet could significantly affect Worldwide climate and sea height. This research aims to develop a coupled model to assess rising sea levels caused by the thawing of the Greenland Ice Sheet, incorporating factors such as global warming, glacier volume, hydrothermal expansion, isostatic rebound, ice dynamics, changes in the gravitational field, and the absorption and release of methane gas. Additionally, the paper investigates the hazards connected to melting glaciers exacerbating global warming. This research provides a crucial foundation for forecasting the long-term impacts of the Greenland Ice Sheet's melting on global climate change.

In What Ways Might Physical Tipping Points in the Climate System Pose Security Problems Now and in the Future?

This paper analyzes physical tipping points in the climate system and their implications for national security, food security and social stability. Physical tipping points are critical states in the climate system that, once passed, lead to irreversible, rapid, and self-accelerating changes. Major tipping points include melting glaciers and rising sea levels, the collapse of terrestrial ecosystems, and an increase in the frequency and intensity of climate extremes. The paper explores the far-reaching impact of these tipping points on security issues, proposes countermeasures and policy recommendations by analyzing the case of Arctic climate change on Russian security, and emphasizes the importance of interdisciplinary cooperation and policy responses to reduce the risks posed by climate change.

Local sources versus long-range transport of organic contaminants in the Arctic: future developments related to climate change

Climate change leads to releases of persistent organic pollutants and chemicals of emerging concern as glaciers melt and permafrost thaws. Increased human activity in the Arctic may enhance local emissions of potentially problematic chemicals.

Diversity and biogeography of the bacterial microbiome in glacier-fed streams

The rapid melting of mountain glaciers and the vanishing of their streams is emblematic of climate change1,2. Glacier-fed streams (GFSs) are cold, oligotrophic and unstable ecosystems in which life is dominated by microbial biofilms2,3. However, current knowledge on the GFS microbiome is scarce4,5, precluding an understanding of its response to glacier shrinkage. Here, by leveraging metabarcoding and metagenomics, we provide a comprehensive survey of bacteria in the benthic microbiome across 152 GFSs draining the Earth’s major mountain ranges. We find that the GFS bacterial microbiome is taxonomically and functionally distinct from other cryospheric microbiomes. GFS bacteria are diverse, with more than half being specific to a given mountain range, some unique to single GFSs and a few cosmopolitan and abundant. We show how geographic isolation and environmental selection shape their biogeography, which is characterized by distinct compositional patterns between mountain ranges and hemispheres. Phylogenetic analyses furthermore uncovered microdiverse clades resulting from environmental selection, probably promoting functional resilience and contributing to GFS bacterial biodiversity and biogeography. Climate-induced glacier shrinkage puts this unique microbiome at risk. Our study provides a global reference for future climate-change microbiology studies on the vanishing GFS ecosystem.

Distributed energy balance, mass balance and climate sensitivity of upper Chandra Basin glaciers, western Himalaya

Abstract Glacier and snow melt are the primary sources of water for streams, and rivers in upper Indus region of the western Himalaya. However, the magnitude of runoff from this glacierized basin is expected to vary with the available energy in the catchment. Here, we used a physically based energy balance model to estimate the surface energy and surface mass balance (SMB) of the upper Chandra Basin glaciers for 7 hydrological years from 2015 to 2022. A strong seasonality is observed, with net radiation being the dominant energy flux in the summer, while latent and sensible heat flux dominated in the winter. The estimated mean annual SMB of the upper Chandra Basin glaciers is −0.51 ± 0.28 m w.e. a−1, with a cumulative SMB of −3.54 m w.e during 7 years from 2015 to 2022. We find that the geographical factors like aspect, slope, size and elevation of the glacier contribute towards the spatial variability of SMB within the study region. The findings reveal that a 42% increase in precipitation is necessary to counteract the additional mass loss resulting from a 1°C increase in air temperature for the upper Chandra Basin glaciers.

Glacial melting explained lake expansion toward drying climate phase on the Tibetan Plateau

Glacial melting explained lake expansion toward drying climate phase on the Tibetan Plateau

Lake pulses driven by glacier melting and climate variability

Lake pulses driven by glacier melting and climate variability

2022 Floods in Balochistan and the Socio-Economic Context of the Region

Pakistan has been hit hard by floods in recent decades. Heavy floods are becoming increasingly common in Pakistan as a result of glaciers melting and exceptional rainfall during monsoon seasons (Hussain et al. 2020). Because it relies on agricultural production, floods pose the greatest threat to the agricultural sector. More than twenty big floods have occurred in Pakistan since its independence, according to a study by the Federal Flood Commission (Tariq and Van De Giesen 2012). The researcher counted five in Pakistan's first decade, five in the 1970s, four in the 1980s, four in the 1990s, and two in the 2010s. More than 500,000 square kilometers of land were damaged by these floods, 12,000 people were killed, and an annual economic loss of 39 billion dollars was incurred. Of all the economic sectors, the one that has been most hit hard is agriculture, which provides the majority of Pakistanis with their daily sustenance. Pakistan has never had a flood as destructive as the one that occurred in 2010. Information gathered by the NDMA indicates that both public and private infrastructure, including roads, railways, bridges, schools, and crops covering millions of acres, were devastated (Mahmood and Hassan 2022). 728,193 dwellings were damaged, more than 2000 people were killed, and there was an economic loss of almost 578 billion USD.

Сутність і зміст кліматичного фінансування

Introduction. The present day is characterized by the destructive consequences of climate change, such as rising temperatures, prolonged droughts, melting glaciers, sea-level rise, catastrophic floods, extreme weather events, and emergencies; biodiversity loss; increasing forest fire risks; declining land productivity; crop failures; reduced eco-friendliness of agricultural products; degradation of fish stocks; increased morbidity and mortality; limited tourism; migration, and humanitarian issues such as loss of property and livelihoods. It can be stated that there is a triple planetary crisis: climate change, biodiversity loss, and environmental pollution. Consequently, the global community&amp;apos;s agenda includes counteracting these negative consequences for humanity – not only minimizing the negative impact but also restoring ecosystems. Problem Statement. Achieving these goals is impossible without proper financial support, which is feasible primarily through a clear understanding of the essence, content, and functions of climate financing, identifying its directions and types, and developing a conceptual model for climate financing. Objective. To define the essence and content of climate financing. Methods. A systematic approach, monographic and historical methods, methods of generalization, comparative and expert analysis were used. Results. Approaches to interpreting climate financing have been clarified, its significance, essence, and content have been identified. The authors present definitions of the terms «climate finance» and «climate financing», a classification of its types, and directions of climate financing. Conclusions. Taking into account such components of climate financing as funding for public climate, environmental, industrial, and energy policies that promote the implementation of projects for prevention / mitigation / adaptation to climate change / restoration / transformation; financing public / private / mixed climate investments; and elements of the financial system related to climate finance will enable the effectiveness of measures in combating the negative consequences of climate change.

The Impact of Climate Change on Human Security: Wars and Terrorism

The critical security studies should be not to establish "objective truth" but to enable a broader understanding of security based on respect for specific theoretical and political starting points in its conceptualization. Issues of environmental security and environmental protection are issues of overall security because they directly cause: open conflicts, have the potential to destabilize the regime, can lead to the displacement of the population, and the disintegration of the states. Regarding the geopolitical consequences of climate change, climate change consequences, such as global warming, rising sea levels, droughts, melting glaciers, and many others, significantly impact the world geopolitics. The level of conflict between states depends on how strong the ties and common interests of the entire region, states and globally. Some states depend on what the atmosphere will be like in their environment. If they are stable and economically prosperous, so will they affect neighboring countries. When climate change has reduced living resources, the economic framework played a much more critical role than religion in joining terrorist organizations. There is a need for research initiatives on how modern technologies, on the one hand, and the involvement of the younger generations and minorities on the other, can be used and increased as ways to strengthen communities' resilience to disasters and ensure an effective, comprehensive, and sustainable approach. Quality governance and leadership in the field of climate change is crucial for environmental safety.