An unshakable carbon budget for the Himalaya

Abstract

The erosion and weathering of mountain ranges exert a key control on the long-term ( 105 -10 6 yr) cycling of carbon between the Earth's surface and the crust. The net carbon budget of a mountain range reflects the co-existence of multiple carbon sources and sinks, with corresponding fluxes remaining difficult to quantify. Uncertain responses of these carbon fluxes due to the stochastic nature of erosional processes further complicates the extrapolation of short-term observations to longer, climatically relevant timescales. Here, we quantify the evolution of the organic and inorganic carbon fluxes in response to the 2015 Gorkha earthquake (Mw 7.8) in the Central Himalaya. We find that the Himalayan erosion acts as a net carbon sink mainly due to efficient biospheric organic carbon export. Our highresolution time-series encompassing four monsoon seasons before and after the Gorkha earthquake, reveal that coseismic landslides did not significantly perturb large-scale Himalayan sediment and carbon fluxes. This muted response of the Central Himalaya to a geologically-frequent perturbation such as the Gorkha earthquake further suggests that our estimates are representative of at least interglacial timescales.

The effect of lithology on the relationship between denudation rate and chemical weathering pathways – evidence from the eastern Tibetan Plateau

“…Felsic igneous rocks typically weather more slowly, but silicate weathering in these rocks is also thought to be sensitive to denudation rates (Riebe et al, 2004;West et al, 2005). In contrast, weathering of siliciclastic (meta)sedimentary rocks is often dominated by the dissolution of minor carbonate and sulfides (Anderson et al, 2000;Calmels et al, 2007;Das et al, 2012;Torres et al, 2016;Emberson et al, 2016b;Jacobson and Blum, 2003;Bufe et al, 2021;Blattmann et al, 2019;Spence and Telmer, 2005;Relph et al, 2021), and rapid denudation and exposure of these rocks can drive CO 2 release from weathering (Calmels et al, 2007;Torres et al, 2014Torres et al, , 2016Bufe et al, 2021;Märki et al, 2021;Spence and Telmer, 2005). Carbonate dissolution also dominates weathering of carbonate-rich sediments (Erlanger et al, 2021;Gaillardet et al, 1999, but the role of sulfide oxidation and therefore the impact of carbonate weathering on the long-term CO 2 cycle can be limited in these rocks (Erlanger et al, 2021;Gaillardet et al, 1999Gaillardet et al, , 2018.…”

The role of earthquakes and storms in the fluvial export of terrestrial organic carbon along the eastern margin of the Tibetan plateau: A biomarker perspective

“…Therefore, earthquakes and storms are likely to impact erosion and fluvial transfer of sediments and terrestrial POC in different ways. Previous studies have assessed the role of earthquakes and storms in the erosion and transport fluxes of POC in regions with different climatic and tectonic settings (Clark et al, 2016;Frith et al, 2018;Märki et al, 2021;Qu et al, 2020;Wang et al, 2016). In contrast to these fluxcentric studies, the impacts of earthquake-and rainfall-triggered landslides on the source and characteristics (e.g., degradation) of POC are less clear.…”

Southeastern Tibetan Plateau Growth Revealed by Inverse Analysis of Landscape Evolution Model

“…The world's highest mountains represent a natural laboratory to constrain models that link topography, geodynamic processes, drainages, biodiversity, and climate (Deng & Ding, 2015). Major questions include the timing and configuration of the India‐Asia collision (Bouilhol et al., 2013), plateau growth mechanisms involving lithospheric thickening, delamination, lower crustal flow or surface processes with (or without) interactions between climate and orogeny (e.g., Molnar et al., 2015; Royden et al., 2008; Tapponnier et al., 2001; Yuan et al., 2021), the potential role of the orogen as a major sink of the global carbon cycle (Märki et al., 2021), and the orogen as a cradle, museum, or abiotic driver of biodiversity hotspots when combined with flickering climate trends (Favre et al., 2015).…”