A much touted example of the effects of global warming have been Greenland's glaciers which have been retreating during the Modern Warm Period. Our Earth orbits around a variable star and the Sun has been cooling off recently. This abstract from Nature Geoscience:
Interruption of two decades of Jakobshavn Isbrae acceleration and thinning as regional ocean cools
Jakobshavn Isbrae has been the single largest source of mass loss from the Greenland Ice Sheet over the last 20 years. During that time, it has been retreating, accelerating and thinning. Here we use airborne altimetry and satellite imagery to show that since 2016 Jakobshavn has been re-advancing, slowing and thickening. We link these changes to concurrent cooling of ocean waters in Disko Bay that spill over into Ilulissat Icefjord. Ocean temperatures in the bay’s upper 250 m have cooled to levels not seen since the mid 1980s. Observations and modelling trace the origins of this cooling to anomalous wintertime heat loss in the boundary current that circulates around the southern half of Greenland. Longer time series of ocean temperature, subglacial discharge and glacier variability strongly suggest that ocean-induced melting at the front has continued to influence glacier dynamics after the disintegration of its floating tongue in 2003. We conclude that projections of Jakobshavn’s future contribution to sea-level rise that are based on glacier geometry are insufficient, and that accounting for external forcing is indispensable.
Isbræ is Danish for glacier. The mid 1980s is right when the Modern Warm Period started. This is when we transitioned from worrying about global cooling to worrying about global warming.
Earth is cooling. All the data point to it.
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