What’s Happening in Antarctica?
On February 6 2020, the Argentina-owned Esperanza Research Station, located on the northern Antarctic Peninsula, recorded a temperature reading of 18.3 degrees Celsius, equal to 64.9 degrees Fahrenheit. This is over 10 degrees Fahrenheit higher than the previous warmest reading, taken March 24 2015 at 53.5 degrees (17.5 degrees Celsius), and is the hottest temperature ever recorded for the Antarctic continent. (For comparison, the average temperature of Miami, Florida in the month of February is 64-75 degrees Fahrenheit.)
The Antarctic Peninsula is typically the warmest area of the continent, with its highest temperatures occurring in January and February (summer months in the southern hemisphere); however, the climate rarely exceeds 50 degrees Fahrenheit, or 10 degrees Celsius. Average winter temperatures are also rising, with some studies attributing an increase of nearly 11 degrees Fahrenheit (6 degrees Celsius) since the 1960s.
In fact, the entire Antarctic region- defined as any location further south than 60 degrees latitude- has been steadily warming. According to the World Meteorological Organization, up to 87% of the glaciers of the western Antarctic Peninsula have retreated in the past fifty years. Though Antarctic sea ice has been gradually expanding over the past few decades, a study published in the PNAS journal suggests that this trend has recently reversed, with record lows of Antarctic sea ice recorded in 2017. Overall, up to 25,000 square kilometers (nearly 10,000 square miles) of Antarctic sea ice have been lost over the past seventy years.
What Does This Mean for the Rest of the World?
The Antarctic ice sheet holds enough water to potentially raise global sea level 200 feet (60 meters). While losing the entire ice sheet is a far-fetched worry, warming Antarctic temperatures and the corresponding sea ice and glacier melt does impact rising waters. Up to a quarter of current sea level rise can be contributed to melting Antarctic ice. One area of concern is the West Antarctic Ice Sheet, containing the notably unstable Thwaites Glacier. In 2018, researchers found evidence that a collapse of the West Antarctic Ice Sheet may have contributed to extremely rapid sea level rise during the Eemian interglacial period, 125,000 years ago, under climate conditions only a few degrees warmer than those today.
Melting ice isn’t the only consequence of rising temperatures. Ocean acidification- a phenomenon most commonly referenced in the topic of coral bleaching- is caused by ocean water absorbing carbon dioxide, changing its pH. The Southern Ocean, which surrounds Antarctica, has seen notable increase in concentration of dissolved CO2, putting its ecosystems in danger. Invertebrates such as krill and zooplankton, which form the bedrock for many marine food webs, could experience severe reductions in population. Additionally, cold-water organisms- typically with lower metabolisms and longer lifespans than their tropical counterparts- may be slower to adapt to changing conditions and therefore less likely to survive alterations to their environments. While this may seem like a local issue, many species from around the world- including birds, fish, and whales- migrate to and from the Southern Ocean throughout their lives. Damage to the Antarctic and surrounding ecosystems may have far-reaching global consequences.
Additonal Information:
- It was 65 Degrees in Antarctica This Week : NPR (Feb 2020)
- Antarctica’s Effect on Sea Level Rise in Coming Centuries: NASA (April 2019)
- Quick Facts About Ice Sheets : NSIDC
article by Kayla Windelspecht
image credits:
- Aerial view of Antarctica: Davepape / Public domain
- Ice sheet: Liam Quinn from Canada / CC BY-SA (https://creativecommons.org/licenses/by-sa/2.0)