Improving LSTM hydrological modeling with spatiotemporal deep learning and multi-task learning: A case study of three mountainous areas on the Tibetan Plateau

Journal of Hydrology, Journal Year: 2023, Volume and Issue: 620, P. 129401 - 129401

Published: March 15, 2023

Language: Английский

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TP-River: Monitoring and Quantifying Total River Runoff from the Third Pole

Bulletin of the American Meteorological Society, Journal Year: 2021, Volume and Issue: 102(5), P. E948 - E965

Published: Jan. 18, 2021

Abstract Monitoring changes in river runoff at the Third Pole (TP) is important because rivers this region support millions of inhabitants Asia and are very sensitive to climate change. Under influence change intensified cryospheric melt, has changed markedly TP, with significant effects on spatial temporal water resource distribution that threaten supply food security for people living downstream. Despite some situ observations discharge estimates from state-of-the-art remote sensing technology, total (TRR) TP never been reliably quantified, its response remains unclear. As part Chinese Academy Sciences’ “Pan-Third Environment Study a Green Silk Road,” TP-River project aims construct comprehensive observation network mountain outlets (where leave mountains enter plains) 13 major region, thereby enabling TRR be accurately quantified. The also integrates cryosphere–hydrology modeling investigate long-term relationship between variations westerly/monsoon. Based recent efforts, provides first estimate (656 ± 23 billion m 3 ) annual 2018. varies widely different rivers, ranging 2 176 , higher values mainly corresponding Indian monsoon domain, rather than westerly domain.

Language: Английский

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Vanishing Glaciers at Southeast Tibetan Plateau Have Not Offset the Declining Runoff at Yarlung Zangbo

Geophysical Research Letters, Journal Year: 2021, Volume and Issue: 48(21)

Published: Oct. 19, 2021

Abstract The Third Pole experiences accelerated glacier retreating particularly in the eastern‐Himalaya, coinciding with a decrease of monsoon‐precipitation early 21st century. extent to which vanishing abundant maritime glaciers buffer declining precipitation‐runoff remains unclear. Here, state‐of‐the‐art enthalpy‐based distributed cryosphere‐hydrology model and first‐hand hydrometeorology observations at Motuo (latest accessible Chinese county), we carefully examine Yarlung Zangbo basin along Himalayas. We find that during 1998–2019, rising downstream runoff (lower Nuxia; +6.40 × 10 8 m 3 /yr) offsets dropping upstream (upper −6.89 /yr); however, only marginal contribution from eastern‐Himalaya Nyainqêntanglha glaciers. During dry illustrates limited melt (15.7 mm/yr) dominated snow (78.8 mm/yr); while much larger humid (144.8 mm/yr for 219.1 melt). From 1981 2019, observe glacier‐to‐snow transition both due degradation growing nonmonsoon‐season precipitation.

Language: Английский

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Modeling glacio-hydrological processes in the Himalayas: A review and future perspectives

Geography and sustainability, Journal Year: 2024, Volume and Issue: 5(2), P. 179 - 192

Published: Jan. 13, 2024

The Himalayas and their surrounding areas boast vast glaciers rivaling those in polar regions, supplying vital meltwater to the Indus, Ganges, Brahmaputra rivers, supporting over a billion downstream inhabitants for drinking, power, agriculture. With changing runoff patterns due accelerated glacial melt, understanding projecting glacio-hydrological processes these basins is imperative. This review assesses evolution, applications, key challenges diverse glacio-hydrology models across Himalayas, varying complexities like ablation algorithms, glacier dynamics, ice avalanches, permafrost. Previous findings indicate higher melt contributions annual Indus compared Ganges Brahmaputra, with anticipated peak melting latter basins—having less cover—before mid-21st century, contrasting delayed expected basin its larger area. Different modeling studies still have large uncertainties simulated components Himalayan basins; projections of future time vary at different Himalaya sub-basins under CMIP scenarios. We also find that lack reliable meteorological forcing data (particularly precipitation errors) major source uncertainty basins. Furthermore, permafrost degradation compounds challenges, complicating assessments freshwater availability. Urgent measures include establishing comprehensive situ observations, innovating remote-sensing technologies (especially monitoring), advancing integrate glacier, snow, processes. These endeavors are crucial informed policymaking sustainable resource management this pivotal, glacier-dependent ecosystem.

Language: Английский

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Snow as an Important Natural Reservoir for Runoff and Soil Moisture in Northeast China

Journal of Geophysical Research Atmospheres, Journal Year: 2020, Volume and Issue: 125(22)

Published: Oct. 26, 2020

Abstract As one of the major agricultural regions in world, water scarcity problems Northeast China have drawn much attention recently. Because cold and long winter period, snow is an important component hydrological system. Yet few studies been conducted to systematically assess its role. This study quantified effects on runoff soil moisture entire region a 30‐year time period (1982–2011) for first time. A energy budget‐based distributed biosphere model with improved physics after calibration validation employed. Standardized Snow depth Index (SSdI) also proposed quantify variations. Result shows that contributes 11% annually average 66% 33% April May (main months crop planting). Soil could decrease by at least 20% March–May if there would be no snow, agriculture area suffers more than other regions. We found SSdI indicative standardized index spring, particularly useful supporting management agriculture. These results indicate performs like reservoir: redistribute resources among months. provides unique insights into importance region. The improve awareness it worth paying this

Language: Английский

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Guidelines for cold‐regions groundwater numerical modeling

Wiley Interdisciplinary Reviews Water, Journal Year: 2020, Volume and Issue: 7(6)

Published: July 8, 2020

Abstract The impacts of ongoing climate warming on cold‐regions hydrogeology and groundwater resources have created a need to develop models adapted these environments. Although permafrost is considered relatively impermeable flow, thaw may result in potential increases surface water infiltration, recharge, hydrogeologic connectivity that can impact northern resources. To account for feedbacks, include the dynamic effects freezing thawing ground properties thermal regimes been recently developed. However, are more complex than traditional numerical due inclusion nonlinear freeze–thaw processes boundary conditions. As such, their use date has limited small community modeling experts. This article aims provide guidelines tips those with previous experience. categorized under: Engineering Water > Methods Science Hydrological Processes

Language: Английский

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Understanding the mass, momentum, and energy transfer in the frozen soil with three levels of model complexities

Hydrology and earth system sciences, Journal Year: 2020, Volume and Issue: 24(10), P. 4813 - 4830

Published: Oct. 12, 2020

Abstract. Frozen ground covers a vast area of the Earth's surface and it has important ecohydrological implications for cold regions under changing climate. However, is challenging to characterize simultaneous transfer mass energy in frozen soils. Within modeling framework Simultaneous Transfer Mass, Momentum, Energy Unsaturated Soil (STEMMUS), complexity soil heat model varies from basic coupled (termed BCM) advanced (ACM), and, furthermore, explicit consideration airflow (ACM–AIR). The impact different complexities on understanding mass, momentum, was investigated. performance simulating water latent flux evaluated over typical Tibetan plateau meadow site. Results indicate that ACM considerably improved simulation moisture, temperature, flux. analysis budget reveals improvement temperature simulations by attributed its physical vapor flow thermal effect flow, with former mainly functioning above evaporative front latter dominating below front. contribution airflow-induced transport (driven air pressure gradient) total fluxes negligible. Nevertheless, given airflow, effects were enhanced during freezing–thawing transition period.

Language: Английский

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Warming winter, drying spring and shifting hydrological regimes in Northeast China under climate change

Journal of Hydrology, Journal Year: 2022, Volume and Issue: 606, P. 127390 - 127390

Published: Jan. 3, 2022

Language: Английский

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Advances in modelling large river basins in cold regions with Modélisation Environmentale Communautaire—Surface and Hydrology (MESH), the Canadian hydrological land surface scheme

Hydrological Processes, Journal Year: 2022, Volume and Issue: 36(4)

Published: March 22, 2022

Abstract Cold regions provide water resources for half the global population yet face rapid change. Their hydrology is dominated by snow, ice and frozen soils, climate warming having profound effects. Hydrological models have a key role in predicting changing but are challenged cold regions. Ground‐based data to quantify meteorological forcing constrain model parameterization limited, while hydrological processes complex, often controlled phase change energetics. River flows impacted poorly quantified human activities. This paper discusses scientific technical challenges of large‐scale modelling region systems reports recent developments, focussing on MESH, Canadian community land surface scheme. New process representations include improved blowing snow transport sublimation, lateral land‐surface flow, prairie pothole pond storage dynamics, ground infiltration thermodynamics, glacier modelling. algorithms represent management multistage reservoir operation. Parameterization has been supported field observations remotely sensed data; new methods parameter identification used evaluate uncertainty support regionalization. Additionally, MESH linked broader decision‐support frameworks, including river simulation forecasting. The also various applications Saskatchewan Mackenzie basins western Canada (0.4 1.8 million km 2 ). These arise glaciated mountain headwaters, partly underlain permafrost, remote incompletely understood forested, wetland, agricultural tundra ecoregions. illustrate current capabilities limitations modelling, extraordinary prediction, need overcoming biases sets, which can disproportionate effects simulated hydrology.

Language: Английский

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Impacts of frozen ground degradation and vegetation greening on upper Brahmaputra runoff during 1981–2019

International Journal of Climatology, Journal Year: 2023, Volume and Issue: 43(8), P. 3768 - 3781

Published: March 2, 2023

Abstract The Tibetan Plateau (TP) contains the largest permafrost region in mid–low latitudes and area of glaciers outside polar regions. In recent decades, this has experienced vegetation greening (e.g., increasing leaf index) due to climate change. As exorheic river on TP, Upper Brahmaputra Basin (UBB) is very sensitive change, experiencing humidifying significant warming. study, we investigated spatiotemporal variability frozen ground over last four decades UBB explored how these changes have impacted runoff using a water‐ energy‐budget distributed hydrological model (WEB‐DHM). We found that almost 50% transformed into seasonally or unfrozen from 1981 2019 with great improvement index (LAI). Based variable‐controlling approach (set air temperature unchanged), revealed degradation caused an average 9.3 billion m 3 water loss per year, accounting for 5.4% total runoff, even if can increase resources at early stage. However, decline by 10.9 (6.4%) annually enhanced evapotranspiration. These findings highlight it critical understand mitigate impacts changing vegetation, when managing availability ecosystem conservation under rapid

Language: Английский

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