Spatial variations in the warming trend and the transition to more severe weather in midlatitudes

Abstract

Due to various feedback processes called Arctic amplification, the high-latitudes’ response to increases in radiative forcing is much larger than elsewhere in the world, with a warming more than twice the global average. Since the 1990’s, this rapid warming of the Arctic was accompanied by no-warming or cooling over midlatitudes in the Northern Hemisphere in winter (the hiatus). The decrease in the thermal contrast between Arctic and midlatitudes has been connected to extreme weather events in midlatitudes via, e.g., shifts in the jet stream towards the equator and increases in the probability of high-latitude atmospheric blocking. Here we present an observational attribution study showing the spatial structure of the response to changes in radiative forcing. The results also connect the hiatus with diminished contrast between temperatures over regions in the Arctic and midlatitudes. Recent changes in these regional warming trends are linked to international actions such as the Montreal Protocol, and illustrate how changes in radiative forcing can trigger unexpected responses from the climate system. The lesson for climate policy is that human intervention with the climate is already large enough that even if stabilization was attained, impacts from an adjusting climate are to be expected.

Long‐term responses to large‐scale disturbances: spatiotemporal variation in gastropod populations and communities

“…Nonetheless, the effects of these disturbances are spatially variable. General trends in warming may not be experienced by all points on the LFDP in the same way, depending on their slope, aspect and other features of the surrounding landscape that affect local temperature (Estrada et al 2021). Similarly, hurricanes are dynamic storms whose effects on local habitats depend on their directionality as well as on slope, aspect and the age and composition of trees (Uriarte et al 2004, 2019, Muscarella et al 2019).…”

Anthropogenic influence on extremes and risk hotspots

“…This induces higher probabilities of atmospheric blocking and the occurrence of persistent heat waves and extreme rainfall events 16 . A recent study linked WACCE to the spatial pattern of anthropogenic warming on temperature changes, providing an explanation for WACCE and the observed changes in extreme events in mid-latitudes 17 . Differential warming between hemispheres also has important implications on precipitation patterns in the tropics and changes in the frequency and magnitude of extreme events by changing key features of the intertropical convergence zone (ITCZ); e.g., location, width, and circulation strength 18 .…”

Winter severity affects occupancy of spring‐ and summer‐breeding anurans across the eastern United States

“…At the same time, anthropogenic-driven warming in the Arctic can lead to increases in severe winter weather events in mid-latitude regions of the US (Estrada et al, 2021). Winter temperature changes in the southeast US have been smaller and more variable than changes in the northeast (Vose et al, 2017).…”

“…Average winter air temperatures have increased by 0.7°C in the northeast US over the past century, while the number of days with snow cover per year have decreased by over one week (O'Connor & Rittenhouse, 2016). At the same time, anthropogenic‐driven warming in the Arctic can lead to increases in severe winter weather events in mid‐latitude regions of the US (Estrada et al, 2021). Winter temperature changes in the southeast US have been smaller and more variable than changes in the northeast (Vose et al, 2017).…”