Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment - AWARE

• West Antarctica is one of the most rapidly warming regions on Earth, and this warming is closely connected with global sea level rise.
• West Antarctic warming does not yet have a comprehensive explanation; dynamical mechanisms may vary from one season to the next and these mechanisms very likely involve complex tele connections with subtropical and tropical latitudes.
  

About Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment – AWARE

• It has been nearly half a century since scientists have collected extensive climate or atmospheric data from the West Antarctic Ice Sheet (WAIS). But late last year, scientists from the U.S. Department of Energy’s (DOE) embarked on a new project that will lead to a better understanding of how much of the sun’s light and the atmosphere’s heat radiation reach the Antarctic surface—variables that affect temperature patterns and ice melt throughout the region.
• This new project is Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment – AWARE
• The AWARE team will use instruments deployed by ARM to the McMurdo Station in Antarctica and the ice-core drilling station at the WAIS—one of the most remote science-based stations on Earth.
• These instruments will gather measurements on cloud properties and their effects on atmospheric radiation at the surface and many other factors such as temperature and winds.
• An aerosol observing system—a mobile atmospheric sampling station will also measure aerosols that affect the formation of clouds.
• The instruments will not be measuring long enough to look at the effects of climate change on Antarctica. However, they will be able to look at weather patterns and the processes affecting how solar and thermal energy impact the surface energy balance, which impacts ice melt and, consequently, sea level rise.
• The temperature gradient between the equator and the poles essentially drives the atmospheric circulation in the southern hemisphere in the form of three north-south systems: the polar cell, the mid-latitude Ferrel cell and the tropical Hadley cell. These cells are dynamically linked together.
• The project will observe how climate change affects the polar region as it has been determined that when the polar region warms, the location of the boundary between the polar and Ferrel cells will change, along with the strength of circulation in both cells.
• During the study, scientists have observed that a change in Antarctic cloud properties that led to a warming of Antarctica weakened the Southern Hemisphere Ferrel cell, and allowed the Hadley Cell on the other side to strengthen, which in turn resulted in more rainfall due to increased latent heat release over Southern Hemisphere tropical regions.
• An expanding Hadley cell is generally expected to result from a globally warming atmosphere, so the Antarctic warming from cloud property change is a positive feedback on a warming climate.
• Another important feature being studied is the winds that traverse in the form of storm tracks across Antarctica’s atmosphere and their effect on Antarctica’s climate. However, one established trend due to global warming is the slight southward shift of the storms and the intrusion of warm air which led to the breaking away of a large ice-shelf. Also, the frequency of warm and moist air intrusions over West Antarctica generated by storms in the Ross and western Amundsen Seas, is a hypothesis under study by AWARE.
   

By: Vishal