We used Planet Labs PlanetScope orthotile surface reflectance imagery from the Dove-R and SuperDove sensors, provided through the NASA Commercial Smallsat Data Acquisition (CSDA) program. Shown are photographs of water bodies and the surrounding landscapes within each region. Maxar's Quickbird, WorldView-2 and -3 platforms offer unparalleled image clarity at resolutions 15% surface water (Nitze et al., 2018).ĭelta Junction (DJ), Fairbanks (FB), Yukon Flats (YF), and Yukon-Kuskokwim Delta (YKD) case study regions. The capacities of commercial satellite platforms have expanded considerably in recent years, providing new opportunities for monitoring water bodies. The prevalence and importance of small water bodies call for novel mapping approaches that utilize advancements in very high-resolution remote sensing. Since existing methods often fail to detect these small water features, CH 4 budgets likely underestimate emissions of this potent greenhouse gas (Walter Anthony et al., 2018). Undetected ponds introduce high uncertainty in estimations of CH 4, as ponds tend to be hotspots for CH 4 production (Negandhi et al., 2013 Wik et al., 2016). Instead, past efforts have been biased toward lakes (Carroll & Loboda, 2017 DeVries et al., 2017 Pekel et al., 2016) and many water maps with high spatial resolutions are temporally static (Messager et al., 2016 Verpoorter et al., 2014). Many optical and active radar sensors used for water mapping do not have the requisite spatial or temporal resolutions to detect ponds and track the seasonality of their areal extent (Carroll & Loboda, 2017 DeVries et al., 2017 Du et al., 2019). Ponds can be much more vulnerable to rapid change relative to lakes (Downing, 2010), yet they are often unaccounted for in existing surface water maps because of detection limits in remote sensing imagery (Cooley et al., 2019 Wangchuk & Bolch, 2020). Here we define ponds as water bodies 0.01 km 2, following the standard area threshold used in other studies (Holgerson & Raymond, 2016 Muster et al., 2017 Verpoorter et al., 2014). Surface area is a key attribute of water bodies and is related to their abundance, spatiotemporal variability, and methane (CH 4) emissions. High latitude lakes and ponds are heavily impacted by climate change (Webb et al., 2022 Xu et al., 2022), and many studies report severe changes in open water extent following shifts in precipitation patterns, loss of sub-surface permafrost, land collapse, and other climate-caused ecosystem disturbances (Arp et al., 2020 Bring et al., 2016 Finger-Higgens, 2022 Jones et al., 2011 Smith et al., 2005 Watts et al., 2014). In boreal and tundra regions, lakes and ponds comprise a much greater fraction (Muster et al., 2017 Verpoorter et al., 2014), exceeding 20% coverage in some areas (Arp et al., 2020 Carroll & Loboda, 2017 Cooley et al., 2019). They also play key roles in biogeochemical cycling and greenhouse gas emissions (Huotari et al., 2011 Kortelainen et al., 2020 Wik et al., 2016). These freshwater ecosystems support species diversity (Strayer & Dudgeon, 2010) and are sources of clean water for human populations (Ho & Goethals, 2019). Lakes and ponds make up at least 3% of Earth's land surface (Downing, 2010 Downing et al., 2006 Messager et al., 2016 Verpoorter et al., 2014).
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