Multiscale modeling of coupled thermo-hydro-mechanical behavior in ice-bonded granular media subject to freeze-thaw cycles

Computers and Geotechnics, Journal Year: 2024, Volume and Issue: 171, P. 106349 - 106349

Published: April 29, 2024

Language: Английский

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Glaciers determine the sensitivity of hydrological processes to perturbed climate in a large mountainous basin on the Tibetan Plateau

Hydrology and earth system sciences, Journal Year: 2024, Volume and Issue: 28(3), P. 669 - 689

Published: Feb. 15, 2024

Abstract. The major rivers on the Tibetan Plateau supply important freshwater resources to riparian regions but have been undergoing significant climate change in recent decades. Understanding sensitivities of hydrological processes is for water resource management, large divergences exist previous studies because uncertainties models and projection data. Meanwhile, spatial pattern local was poorly explored despite strong heterogeneity Plateau. This study adopted perturbation method analyze a typical mountainous basin (Yarlung Tsangpo River, YTR) change. We utilized tracer-aided model Tsinghua Representative Elementary Watershed-Tracer-aided version (THREW-T) simulate cryospheric YTR basin. Multiple datasets internal stations were used validate provide confidence baseline simulation sensitivity analysis. Results indicated that (1) THREW-T performed well simulating streamflow, snow cover area (SCA), glacier mass balance (GMB) stream isotope, ensuring good representation key reasonable estimation runoff components. acceptably streamflow at eight located mainstream two tributaries, indicating reflected by model. (2) Increasing temperature led decreasing annual runoff, smaller inter-annual variation, more even intra-annual distribution an earlier maximum runoff. It also influenced regime increasing contributions rainfall melt overland subsurface snowmelt precipitation had opposite effect temperature. (3) response varied significantly, with changing rate −18.6 % 54.3 5∘ warming. ratio (GAR) dominant factor both perturbed precipitation. Some non-monotonic perturbation, which represented most dynamic within basin, as they kept shifting between energy- water-limited stages. GAR mean (MAP) linear relation formed boundary different trends GAR–MAP plot.

Language: Английский

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Projecting sediment export from two highly glacierized alpine catchments under climate change: exploring non-parametric regression as an analysis tool

Hydrology and earth system sciences, Journal Year: 2024, Volume and Issue: 28(1), P. 139 - 161

Published: Jan. 9, 2024

Abstract. Future changes in suspended sediment export from deglaciating high-alpine catchments affect downstream hydropower reservoirs, flood hazard, ecosystems and water quality. Yet, quantitative projections of future have so far been hindered by the lack process-based models that can take into account all relevant processes within complex systems determining dynamics at catchment scale. As a promising alternative, machine-learning (ML) approaches recently successfully applied to modeling yields (SSYs). This study is first, our knowledge, exploring approach derive until year 2100. We employ quantile regression forest (QRF), which proved be powerful method model past SSYs previous studies, for two nested glaciated Ötztal, Austria, above gauge Vent (98.1 km2) Vernagt (11.4 km2). predictors, we use temperature precipitation (EURO-CORDEX) discharge (AMUNDSEN physically based hydroclimatological snow model) gauges. address uncertainties associated with known limitation QRF underestimates expected if values projection period exceed range represented training data (out-of-observation-range days, OOOR). For this, assess frequency extent these exceedances sensitivity resulting mean annual concentration (SSC) estimates. examine SSY trends, estimated timing peak seasonal distribution. Our results show OOOR points are small before 2070 (max. 3 % change SSC). Results after treated more cautiously as occur frequently, glaciers projected (nearly) vanished then some projections, likely substantially alters area. The suggest decreasing both gauges coming decades, regardless emission scenario, implies has already passed or underway. linked substantial decreases volumes, especially during glacier melt phase late summer, result increasing temperatures thus shrinking glaciers. Nevertheless, high(er) response heavy summer precipitation, developments would need considered managing sediments, well e.g., hazard. While chose predictors act proxies sediment-relevant processes, studies encouraged try include geomorphological explicitly, connectivity, landsliding, rockfalls vegetation colonization, could improve reliability projections.

Language: Английский

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Accelerated River Meander Migration on the Tibetan Plateau Caused by Permafrost Thaw

Geophysical Research Letters, Journal Year: 2025, Volume and Issue: 52(1)

Published: Jan. 5, 2025

Abstract The migration of rivers in permafrost landscapes has critical implications for riverine infrastructure, ecosystem stability, and carbon cycling, yet its magnitude underlying mechanisms remain poorly understood. Here, we leverage four decadal satellite imagery, hydrological observations, modeling to investigate meander dynamics on the Tibetan Plateau. Our data show that rates have increased by 34.6% from 1987 2022, response combined effects discharge, riverbank destabilization driven ground ice melt extended thawing days (increased 35 days). In contrast, flowing across seasonally frozen exhibited a decline rate 11.1%, vegetation greening stabilization. future warming climate Plateau, are anticipated further accelerate, potentially threatening infrastructure safety aquatic ecosystems, intensifying cycle.

Language: Английский

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Soil property changes following a thaw-induced mass movement event in the permafrost region of the Qinghai–Tibetan Plateau

CATENA, Journal Year: 2025, Volume and Issue: 252, P. 108850 - 108850

Published: March 1, 2025

Language: Английский

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Global warming changes patterns of runoff and sediment flux in Tibetan Yangtze River headwater

Journal of Hydrology, Journal Year: 2025, Volume and Issue: 656, P. 133009 - 133009

Published: March 5, 2025

Language: Английский

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Effects of Changes in Freeze‐Thaw Cycles on Soil Hydrothermal Dynamics and Erosion Degradation Under Global Warming in the Black Soil Region

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(3)

Published: March 1, 2025

Abstract Global warming can change the freeze‐thaw cycles (FTCs) in seasonally frozen ground and influence soil water conservation. This study employed an enhanced SWAT‐FT (Soil Water Assessment Tool‐FTCs) model to explore effects of different future climate scenarios on FTCs, hydrothermal dynamics, erosion Upper Mississippi River Basin (UMRB), a typical black region with ground. Results suggested that could more representatively simulate dynamics compared SWAT. The simulations revealed temperature 0–100 cm layers UMRB increase by approximately 2°C–4°C during FTCs period under SSP5‐8.5 mid late 21st century, decreasing freezing days (FD) even absence some southern zones, but FD for central zones. These changes were affected air temperature, content, snow cover, resulting three dominant response patterns global UMRB, which lag symmetric northern non‐symmetric rapid alterations due exacerbated early spring after 2.3 times 2071–2100 baseline scenario (1985–2014). Moreover, pattern converted from “dual‐peak” “single‐peak” April or May, increasing challenges control.

Language: Английский

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Impacts of climate change and freeze–thaw cycles on water and sediment fluxes in the headwater region of the Yangtze River, Qinghai–Tibet Plateau

CATENA, Journal Year: 2023, Volume and Issue: 227, P. 107112 - 107112

Published: March 31, 2023

Language: Английский

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Peak Cenozoic warmth enabled deep-sea sand deposition

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Feb. 8, 2023

Abstract The early Eocene (~ 56–48 million years ago) was marked by peak Cenozoic warmth and sea levels, high CO 2 , largely ice-free conditions. This time has been described as a period of increased continental erosion silicate weathering. However, these conclusions are based on geochemical investigation marine mudstones carbonates or study intermontane Laramide basin settings. Here, we evaluate the coarse siliciclastic response to Paleogene hothouse climatic oceanographic We compile an inventory documented sand-rich (turbidite) deep-marine depositional systems, recording 59 instances turbidite systems along nearly all margins despite globally-elevated levels. Sand-rich were widespread active (42 instances), but also passive (17 instances). Along margins, 13 17 associated with known Eocene-age fluvial consistent clastic warming. suggest that sedimentary basins preserve records extremes. in addition control eustasy tectonism, climate-driven increases sediment supply (e.g., drainage integration, global rainfall, denudation) may significantly contribute distribution volume coarse-grained deposition level.

Language: Английский

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Unchanged frequency and decreasing magnitude of outbursts from ice-dammed lakes in Alaska

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Oct. 2, 2023

Abstract Glacial lakes can form and grow due to glacial retreat, rapid lake drainage produce destructive floods. Outburst flood compilations show a temporal increase in frequency; however, recent studies highlight the role of observational bias, creating uncertainty about current future glacial-lake hazards. Here, we focus on Alaska region, which generated third previously documented outbursts globally. Using multitemporal satellite imagery, 1150 drainages from 106 ice-dammed between 1985 2020. Documented events became more frequent over time, accounting for increasing image availability reveals no significant occurred. Most decreased area volume, suggesting reduction regional hazard. Our satellite-based approach 60% 35-year period than had been 100 years. This suggests that outburst floods have historically underreported warrants systematic study other regions.

Language: Английский

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