A look at weather extremes and the big-picture climate connections.

Video: Extreme Weather and Rapid Arctic Warming

Recently I reported on a study showing links between rapid Arctic climate change and shifts in the jet stream throughout the Northern Hemisphere. The study, led by Jennifer Francis of Rutgers University, suggests that there may be an Arctic connection to some extreme weather events, particularly ones that result from stuck, or "blocked," weather patterns.

The study shows that by changing the temperature balance between the Arctic and mid-latitudes, rapid Arctic warming is altering the course of the jet stream, which steers weather systems from west to east around the hemisphere. The Arctic has been warming about twice as fast as the rest of the Northern Hemisphere, due to a combination of human emissions of greenhouse gases and unique feedbacks built into the Arctic climate system.

The jet stream, the study states, is becoming “wavier,” with steeper troughs and higher ridges. As a result, weather systems are progressing more slowly, raising the chances for long-duration extreme events, like droughts, floods, and heat waves. 

Over at the Yale Forum on Climate Change and the Media, Pete Sinclair — known for his "climate denial crock of the week" video series — posted a video exploring this study and other recent evidence regarding the causes of extreme weather and climate events. It's worth watching, and features interviews with Dr. Francis, Jeff Masters of Weather Underground, and several other experts. 

« Extreme Planet


By Charles Vigh (Jacksonville, FL 32217)
on May 3rd, 2012

Thank you.  Your presentation was reasonable for explaining the past few years events.  I watch sea level change for understanding gross climate change.  From around the world new information suggests sea level rise along coastlines is from 1.9 millimeters per year to 3.3 millimeters per year.  I suspect the lower number is closer to reality and has been averaging close to an estimated measure of sea level rise for something like 150 + years.  I further suspect that this slow change in sea level rise will continue through this century.  Your presentation focused on the increase in atmospheric moisture due to climate change along with changing patterns of jet streams.  We do not know whether nor to what degree these atmospheric changes are cyclical, but tree ring data suggests that today’s patterns have to some degree occurred in the past.  This complexity could be a subject of a future presentation by you.  I’m waiting for new information from polar upper atmosphere studies to help explain what is going on.

Reply to this comment

Name (required):
Email (required):
Enter the word "climate" in the box below:

[+] View our comment guidelines.

Please note: Comment moderation is enabled. Your comment will not appear until reviewed by Climate Central staff. Thank you for your patience.