02186nas a2200313   4500008004100000022001400041245009000055210006900145260001200214300001800226490000700244520123000251653002201481653002401503653002001527653001701547653001501564100002201579700002101601700002101622700002201643700002201665700002401687700002101711700002501732700002101757700002501778856006901803       2024                        eng d  a2328-427700aResponse of a terrestrial polar ecosystem to the March 2022 Antarctic weather anomaly0 aResponse of a terrestrial polar ecosystem to the March 2022 Anta  c08/2024  ae2023EF0043060 v123 a<p>Record high temperatures were documented in the McMurdo Dry Valleys, Antarctica, on 18 March 2022, exceeding average temperatures for that day by nearly 30&deg;C. Satellite imagery and stream gage measurements indicate that surface wetting coincided with this warming more than 2 months after peak summer thaw and likely exceeded thresholds for rehydration and activation of resident organisms that typically survive the cold and dry conditions of the polar fall in a freeze-dried state. This weather event is notable in both the timing and magnitude of the warming and wetting when temperatures exceeded 0&deg;C at a time when biological communities and streams have typically entered a persistent frozen state. Such events may be a harbinger of future climate conditions characterized by warmer temperatures and greater thaw in this region of Antarctica, which could influence the distribution, activity, and abundance of sentinel taxa. Here we describe the ecosystem responses to this weather anomaly reporting on meteorological and hydrological measurements across the region and on later biological observations from Canada Stream, one of the most diverse and productive ecosystems within the McMurdo Dry Valleys.</p>10aatmospheric river10aclimate variability10aextreme weather10apolar desert10asoil biota1 aBarrett, John, E.1 aAdams, Byron, J.1 aDoran, Peter, T.1 aDugan, Hilary, A.1 aMyers, Krista, F.1 aSalvatore, Mark, R.1 aPower, Sarah, N.1 aSnyder, Meredith, D.1 aWright, Anna, T.1 aGooseff, Michael, N.  uhttps://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023EF004306