Measuring and Attributing Sedimentary and Geomorphic Responses to Modern Climate Change: Challenges and Opportunities

Abstract

Earth-surface-process studies span a vast range of physical landscape settings across deserts, mountains, rivers, coasts, and the cryosphere (Figure 1), and today anthropogenically induced climate change is affecting virtually all of these. Future warming will increasingly impact the geomorphic and sedimentary evolution of essentially all terrestrial and nearshore settings. Anthropogenic influence on Earth's climate has been distinctly evident for only a little over 50 years, since the anomalous global warming signal clearly diverged from natural climate variability around 1970; human influence now dominates strongly over natural solar and volcanic climate effects (Intergovernmental Panel on Climate Change (IPCC, 2014(IPCC, , 2021. Tying physical landscape responses to climate change over any time scale is notoriously difficult due to intrinsic and often highly dynamic natural variability of landscapes, multiple modes of climate variability, and human modification of Earth's surface. Can we identify geomorphic effects of recent, ongoing warming over the last five decades? How will future climate change continue to alter landscape processes? These questions must be answered for societies to prepare appropriately for future, climate-driven hazards to human health and safety, risks to the built environment, security of water-foodenergy systems, consequences to economies, and the preservation of ecosystems and other natural resources. Some landscape responses follow directly from global warming-for example, permafrost thaw, glacier retreat, or thermal rock stresses that result from increasing temperatures (Figure 2)-whereas other landscape responses are secondary, such as shifting coastal position due to sea-level rise and/or sediment-supply changes, or responses to a changing hydrologic cycle. These responses, in turn, alter the movement of geologic and geochemical materials Abstract Today, climate change is affecting virtually all terrestrial and nearshore settings. This commentary discusses the challenges of measuring climate-driven physical landscape responses to modern global warming: short and incomplete data records, land use and seismicity masking climatic effects, biases in data availability and resolution, and signal attenuation in sedimentary systems. We identify opportunities to learn from historical and paleo data, select especially sensitive study sites, and report null results to better characterize the extent and nuances of climate-change effects. We then discuss efforts to improve attribution practices, which will lead to better predictive capabilities. We encourage the Earth-science community to prioritize scientific research on climate-driven physical landscape changes so that societies will be better prepared to manage the effects on health and safety, infrastructure, water-food-energy security, economics, and ecosystems that follow from climate-driven physical landscape change.Plain Language Summary Modern global warming will ultimately affect physical landscape processes virtually everywhere on...

Suspended sediment deposition and sediment yields at Lake Peters, northeast Brooks Range, Alaska: Fluvial‐ and lake‐based approaches

“…Expanding our understanding of Arctic and cold region sediment yields is important for assessing the impacts of rapid environmental change in these especially sensitive and less studied settings (East et al, 2022;Zhang et al, 2022). Societal implications of such change in the Arctic, which can include degraded water quality, riverinecoastal ecological destabilization and altered land-ocean biogeochemical fluxes, may not be fully recognized by scientists, policymakers and community stakeholders.…”

“…Downstream transfers of fluvial suspended sediment are climate responsive, making sediment records useful indicators of catchment‐scale environmental change (East et al, 2022; Hodgkins et al, 2003). In the physical sciences, records of suspended sediment are used for understanding catchment dynamics, applied to environmental reconstructions (Hambley & Lamoureux, 2006; Schiefer et al, 2017), and inform forecasting studies (Gordeev, 2006; Lewis & Lamoureux, 2010; Syvitski, 2002).…”

“…Furthermore, most sediment yields are estimated using fluvial rating curve methods, limiting their time series to the length of monitoring, which in only a couple Arctic studies, to our knowledge, spanned more than a decade (Beel et al, 2018;Bogen & Bønsnes, 2003). In contrast, lakes act as primary sediment sinks, and lake sediment studies can provide longer sediment yield records to improve our understanding of sediment transfer processes and their relation to climate (Desloges & Gilbert, 1994;East et al, 2022;Lamoureux, 2000;Schiefer et al, 2017;Tape et al, 2011). However, most Arctic sediment studies have focused on relating hydroclimatic forcing to records of sediment accumulation from a single sediment core or a few cores.…”

Distribution and Recurrence of Warming‐Induced Retrogressive Thaw Slumps on the Central Qinghai‐Tibet Plateau

“…Previous studies indicate that modern climate change has triggered numerous retrogressive thaw slumps (RTSs) in permafrost landscapes, especially during the thaw season in years with higher air temperatures and precipitation (Lewkowicz & Way, 2019; Luo et al., 2022b). RTSs further increase erosion, sediment fluxes, and thus affect hydropower systems, water quality, and the carbon cycle (East et al., 2022; Li et al., 2021a; Pei et al., 2023a; Zhang et al., 2022a).…”

“…Previous studies indicate that modern climate change has triggered numerous retrogressive thaw slumps (RTSs) in permafrost landscapes, especially during the thaw season in years with higher air temperatures and precipitation (Lewkowicz & Way, 2019;Luo et al, 2022b). RTSs further increase erosion, sediment fluxes, and thus affect hydropower systems, water quality, and the carbon cycle (East et al, 2022;Li et al, 2021a;Pei et al, 2023a;Zhang et al, 2022a).The Qinghai-Tibet Plateau (QTP) contains the largest permafrost region outside the northern circumpolar region and is the key geomorphological unit in Asia that affects the regional and even global climate (Yao et al, 2012;Zou et al, 2017). However, this geomorphological unit is extremely vulnerable to climate change due to elevation-dependent warming and its delicate natural environment (Kuang & Jiao, 2016;Pei et al, 2023b;Pepin et al, 2015).…”