Antarctic Flowering Plants Growing and Spreading at Unprecedented Rates

Current Biology, 14 February 2022

Antarctica’s two native flowering plants – pearlwort and hairgrass – have experienced unprecedented growth over the past decade as a result of rising air temperatures, with longer and wetter summers. These warm summer months also reduce the amount of ice covering the soil. In the South Orkney Islands of Antarctica, these flowering plants have grown bigger and more plentifully over the past decade than at any period since 1960. Pearlwort spread ten times faster between 2009 and 2018 than its average during the previous fifty years, and hairgrass increased by fivefold. Antarctica’s plants are specially adapted to surviving its extreme environment – in particular, tolerating low temperatures, short growing seasons, and dehydration. Over the past decade however, Antarctic summer warming has increased from +0.02C to +0.27C each year. These increasingly mild summer conditions may also make Antarctica increasingly vulnerable to invasion by non-native plant species that could dramatically change local ecosystems, and trigger irreversible wildlife loss. Authors emphasize the importance of preparing conservation strategies, though this ultimately requires reduction of global emissions to curb temperatures and slow cascading effects of climate change on the native biodiversity of Antarctica.