The “Great Dying”: Rapid Warming and Monsoonal Intensification
Contributed to the Abrupt Collapse of Forest-Mire (Glossopteris) Ecosystems in the High Southern Latitudes
Boulder, Colo., USA: The Paleozoic era culminated 251.9 million years ago
in the most severe mass extinction recorded in the geologic record. Known
as the “great dying,” this event saw the loss of up to 96% of all marine
species and around 70% of terrestrial species, including plants and
The consensus view of scientists is that volcanic activity at the end of
the Permian period, associated with the Siberian Traps Large Igneous
Province, emitted massive quantities of greenhouse gases into the
atmosphere over a short time interval. This caused a spike in global
temperatures and a cascade of other deleterious environmental effects.
An international team of researchers from the United States, Sweden, and
Australia studied sedimentary deposits in eastern Australia, which span the
extinction event and provide a record of changing conditions along a
coastal margin that was located in the high latitudes of the southern
hemisphere. Here, the extinction event is evident as the abrupt
disappearance of Glossopteris forest-mire ecosystems that had
flourished in the region for millions of years. Data collected from eight
sites in New South Wales and Queensland, Australia were combined with the
results of climate models to assess the nature and pace of climate change
before, during, and after the extinction event.
Results show that Glossopteris forest-mire ecosystems thrived
through the final stages of the Permian period, a time when the climate in
the region was gradually warming and becoming increasingly seasonal. The
collapse of these lush environments was abrupt, coinciding with a rapid
spike in temperatures recorded throughout the region. The post-extinction
climate was 10–14°C warmer, and landscapes were no longer persistently wet,
but results point to overall higher but more seasonal precipitation
consistent with an intensification of a monsoonal climate regime in the
high southern latitudes.
Because many areas of the globe experienced abrupt aridification in the
wake of the “great dying,” results suggest that high-southern latitudes may
have served as important refugia for moisture-loving terrestrial groups.
The rate of present-day global warming rivals that experienced during the
“great dying,” but its signature varies regionally, with some areas of the
planet experiencing rapid change while other areas remain relatively
unaffected. The future effects of climate change on ecosystems will likely
be severe. Thus, understanding global patterns of environmental change at
the end of the Paleozoic can provide important insights as we navigate
rapid climate change today.
The article was published today in the Geological Society of America
Pace, magnitude, and nature of terrestrial climate change through the
End-Permian Extinction in southeastern Gondwana
T.D. Frank; C.R. Fielding; A.M.E. Winguth; K. Savatic; A. Tevyaw; C.
Winguth; S. McLoughlin; V. Vajda; C. Mays; R. Nicoll; M. Bocking; J.L.
Corresponding author: Tracy Frank (email@example.com), University of
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