Rapid response of silicate weathering rates to climate change in the Himalaya

AbstractGlobal climate is thought to be modulated by the supply of minerals to Earth’s surface. Whereas silicate weathering removes carbon dioxide (CO2) from the atmosphere, weathering of accessory carbonate and sulfide minerals is a geologically relevant source of CO2. Although these weathering pathways commonly operate side by side, we lack quantitative constraints on their co-variation across erosion rate gradients. Here we use stream-water chemistry across an erosion rate gradient of three orders of magnitude in shales and sandstones of southern Taiwan, and find that sulfide and carbonate weathering rates rise with increasing erosion, while silicate weathering rates remain steady. As a result, on timescales shorter than marine sulfide compensation (approximately 106–107 years), weathering in rapidly eroding terrain leads to net CO2 emission rates that are at least twice as fast as CO2 sequestration rates in slow-eroding terrain. We propose that these weathering reactions are linked and that sulfuric acid generated from sulfide oxidation boosts carbonate solubility, whereas silicate weathering kinetics remain unaffected, possibly due to efficient buffering of the pH. We expect that these patterns are broadly applicable to many Cenozoic mountain ranges that expose marine metasediments.

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Opportunities for harnessing the increased contribution of glacier and snowmelt flows in the Ganges basin

Water Policy ◽

10.2166/wp.2013.008 ◽

2013 ◽

Vol 15 (S1) ◽

pp. 9-25 ◽

Cited By ~ 5

Author(s):

Bharat R. Sharma ◽

Devaraj de Condappa

Keyword(s):

Climate Change ◽

Aquifer Recharge ◽

Eastern India ◽

Ganges Basin ◽

Additional Water ◽

Set Up ◽

Tehri Dam ◽

The Ganges ◽

The Impact ◽

The Himalaya

The topography of the Ganges basin is highly variable, with the steep mountainous region of the Himalaya upstream and the large fertile plains in eastern India and Bangladesh downstream. The contribution from the glaciers to streamflows is supposed to be significant but there is uncertainty surrounding the impact of climate change on glaciers. An application of the Water Evaluation and Planning model was set up which contained an experimental glaciers module. The model also examined the possible impacts of an increase in temperature. The contribution from glaciated areas is significant (60–75%) in the Upper Ganges but reduces downstream, falling to about 19% at Farakka. Climate change-induced rise in temperature logically increases the quantity of snow and ice that melts in glaciated areas. However, this impact decreases from upstream (+8% to +26% at Tehri dam) to downstream (+1% to +4% at Farakka). Such increases in streamflows may create flood events more frequently, or of higher magnitude, in the upper reaches. Potential strategies to exploit this additional water may include the construction of new dams/reservoir storage and the development of groundwater in the basin through managed aquifer recharge. The riparian states of India, Nepal and Bangladesh could harness this opportunity to alleviate physical water scarcity and improve productivity.

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Glaciohydrology of the Himalaya-Karakoram

Science ◽

10.1126/science.abf3668 ◽

2021 ◽

pp. eabf3668

Author(s):

Mohd. Farooq Azam ◽

Jeffrey S. Kargel ◽

Joseph M. Shea ◽

Santosh Nepal ◽

Umesh K. Haritashya ◽

...

Keyword(s):

Climate Change ◽

Water Resources ◽

Current Status ◽

Snow Melt ◽

Resources Management ◽

Critical Knowledge ◽

Glacier Melt ◽

Sustainable Water Resources Management ◽

The Himalaya ◽

Sustainable Water Resources

Understanding the response of Himalayan-Karakoram (HK) rivers to climate change is crucial for ~1 billion people who partly depend on these water resources. Policymakers tasked with the sustainable water resources management for agriculture, hydropower, drinking, sanitation, and hazards require an assessment of rivers’ current status and potential future changes. This review demonstrates that glacier and snow melt are important components of HK rivers, with greater hydrological importance for the Indus than Ganges and Brahmaputra basins. Total river runoff, glacier melt, and seasonality of flow are projected to increase until the 2050s, with some exceptions and large uncertainties. Critical knowledge gaps severely affect modeled contributions of different runoff components, future runoff volumes and seasonality. Therefore, comprehensive field- and remote sensing-based methods and models are needed.

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Climate Change Observations of Indigenous Communities in the Indian Himalaya

Weather Climate and Society ◽

10.1175/wcas-d-20-0077.1 ◽

2021 ◽

Vol 13 (2) ◽

pp. 245-257

Author(s):

Vikram S. Negi ◽

Shinny Thakur ◽

Rupesh Dhyani ◽

Indra D. Bhatt ◽

Ranbeer S. Rawal

Keyword(s):

Climate Change ◽

Climate Change Impacts ◽

Indigenous Communities ◽

Western Himalaya ◽

Warming Trend ◽

Indian Himalaya ◽

Climate Anomalies ◽

Change Perceptions ◽

The Himalaya ◽

Instrumental Temperature

AbstractMountains are important global sites for monitoring biological and socioecological responses to climate change, and the Himalaya has some of the world’s most rapid and visible signs of climate change. The increased frequency and severity of climate anomalies in the region are expected to significantly affect livelihoods of indigenous communities in the region. This study documents the perceptions of indigenous communities of climate change in the western Himalaya of India. The study highlights the power of knowledge and understanding available to indigenous people as they observe and respond to climate change impacts. We conducted a field-based study in 14 villages that represent diverse socioecological features along an altitudinal range of 1000–3800 m MSL in the western Himalaya. Among the sampled population, most of the respondents (>95%) agreed that climate is changing. However, people residing at low- and high-altitude villages differ significantly in their perception, with more people at high altitudes believing in an overall warming trend. Instrumental temperature and rainfall from nearby meteorological stations also supported the perception of local inhabitants. The climate change perceptions in the region were largely determined by sociodemographic variables such as age, gender, and income as well as altitude. A logistic regression, which exhibited significant association of sociodemographic characteristics with climate change perceptions, further supported these findings. The study concluded that the climate change observations of local communities can be usefully utilized to develop adaptation strategies and mitigation planning in the Himalayan region.

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Is the climate change mitigation effect of enhanced silicate weathering governed by biological processes?

Global Change Biology ◽

10.1111/gcb.15993 ◽

2021 ◽

Author(s):

Sara Vicca ◽

Daniel Goll ◽

Mathilde Hagens ◽

Jens Hartmann ◽

Ivan A. Janssens ◽

...

Keyword(s):

Climate Change ◽

Climate Change Mitigation ◽

Silicate Weathering ◽

Biological Processes ◽

Change Mitigation

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Cambial phenology in Abies pindrow (Pinaceae) along an altitudinal gradient in northwestern Himalaya

IAWA Journal ◽

10.1163/22941932-bja10007 ◽

2020 ◽

Vol 41 (2) ◽

pp. 186-201

Author(s):

Rayees Malik ◽

Sergio Rossi ◽

Raman Sukumar

Keyword(s):

Climate Change ◽

Altitudinal Gradient ◽

Cell Formation ◽

Growing Season ◽

Wood Formation ◽

Warming Climate ◽

The World ◽

Abies Pindrow ◽

The Himalaya ◽

Impacts Of Climate Change

Abstract Climate change is expected to be heterogeneous across the world, with high impacts on the Himalayan ecosystems. There is a need to precisely document cambial phenology and wood formation in these regions to better understand climate-growth relationships and how trees face a warming climate. This study describes the dynamics of cambial phenology in pindrow fir (Abies pindrow) along its altitudinal gradient in the Himalaya. The stages of xylem phenology, and the duration and rate of wood formation were assessed from anatomical observations during the growing season from samples collected weekly from three sites at various altitudes (2392–2965 m a.s.l.) over two years. There were significant differences in the duration and rate of cell formation along the altitudinal gradient, which decreased at increasing altitudes. The growing season duration decreased by 5.2 and 3.7 days every 100 m of increase in altitude in 2014 and 2015, respectively, while the rate of cell formation decreased from 0.38 and 0.44 cells /day to 0.29 and 0.34 cells/day in 2014 and 2015, respectively. Cell production decreased from 63.3 and 67.0 cells to 38.3 and 45.2 cells with a decrease of 4.3 and 3.8 cells per 100 m increase in altitude in 2014 and 2015, respectively. The higher precipitation in 2015 increased the growth rate and resulted in a higher xylem production. Our findings give new insights into the dynamics of cambial phenology and help in better understanding of the potential impacts of climate change on tree growth and forest productivity of Himalayan forests.

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