Starship Asterisk*

MargaritaMc wrote:Just to join in. Last week we had three days of La Calima (hot sand storm from the Sahara, not nice). This week we have unseasonally low temperatures and thick cloud cover, with a COLD wind...
I really feel sorry for people who are here on holiday.
Margarita

rstevenson wrote:Yesterday in southern Saskatchewan (the mid-prairies in Canada) you could have driven just an hour or two and experienced a blizzard, flooding, and brush fires all in the space of that short drive. What fun they're having.

Here on the east cost we're just having a "normal" late spring. It only seems bad when compared to last year's abnormally early spring.

Rob

We're expecting both Wichita Falls and Oklahoma City to break their record cold high temperatures today. The previous record for Wichita Falls was 53 degrees set in 2005, and for Oklahoma City was 51 set in 1994. Another interesting tidbit, if Will Rogers doesn't climb above 44 degrees before midnight, we will have tied the record for coldest high temperature for the month of May, which was set on May 4, 1935! Quite a year 2013 has been so far!

What Is Going On? Bill Holton writes: "Paul, please explain to readers WHY this is happening? Snow of this magnitude has NEVER been seen in this part of the country in May, or anywhere in the U.S. outside of the Rockies." Bill, snow east of the Rockies, outside of higher terrain in New England, is exceedingly rare, yes - but not totally unprecedented. What we're seeing is consistent with what climate scientists have been predicting for 30 years. As northern latitudes warm the north-south temperature contrast weakens, which triggers a drop in jet stream winds - which become more unstable, with greater north/south swings, what meteorologists call a "high amplitude" pattern. When this happens warm, moist air can be transported unusually far north (helping to rapidly ease drought and trigger record flooding), while unusually cold air can sweep much farther south than usual, sometimes "cutting off" from the main belt of westerly steering winds, causing weather patterns to temporarily stall. In short, the weather has a greater potential to become become stuck.

Proving cause and effect is difficult, at times impossible, but talking with climate scientists there seems to be a strong causal connection between more weather extremes and record warming taking place in the Arctic. 90% of warming is going into the oceans, and some of that warmth is showing up in the Arctic, which has lost 70-75% of its ice volume in 50 years, reaching a record low in September, 2012. A warming Arctic can displace the cold air that should be at the top of the world farther south over Canada, Europe and Asia, setting the stage for more extremes, more head-scratching "Black Swan" weather events.

A blocking pattern (with a warm bubble of high pressure over Greenland) steered Superstorm Sandy into coastal New Jersey on October 29, 2012, which is highly unusual for late October. A blocking pattern resulted in blistering, record-setting heat over much of the USA last summer. Droughts and heatwaves can become even more intense, while (stalled) storms can squeeze out more rain, or snow. Keep in mind there's more water vapor in the air (a 4% increase in 40 years), more fuel for storms, summer and winter. Rain is falling harder during the summer months, and when it does snow, it tends to come down harder. There are few things more complicated and interconnected than weather and climate - more research is required, but it's probably safe to say that we'll see more extremes in the years ahead, more examples of weather on steroids.

Changes in the Arctic are happening much faster than predicted. Richard Alley at Penn State believes some of these changes are taking place 100 years ahead of schedule. Climate scientist James Hansen believes warming of the oceans and atmosphere is equivalent to 400,000 Hiroshima bombs going off every day. We may be undergoing a "phase transition" in the climate system, which is non-linear. Nature rarely moves in a straight line. Alarmist hype? I sure hope so. But the reality: we're in uncharted water when it comes to global changes and impact on local weather.

mjimih wrote:

bystander wrote:
Record low High (48F) yesterday, record low Low (37F) this morning.
Last year at this time we were recording near record Highs.

http://www.startribune.com/weather/blogs/Paul_Douglas_on_Weather.html wrote:

neufer wrote:

mjimih wrote:

bystander wrote:
Record low High (48F) yesterday, record low Low (37F) this morning.
Last year at this time we were recording near record Highs.

http://www.startribune.com/weather/blogs/Paul_Douglas_on_Weather.html wrote:

A globlally warmed Arctic Ocean can't keep it's Northern Polar Springtime Hurricane Hexagon intact.

orin stepanek wrote:It's is finally acting like Spring! I would hope it stayed that way; but the forecast is calling for temps in the 80's by the end of the week. It's time for Spring fever!

Jet stream 2.0
People are asking about recent weather extremes: record drought to historic floods, virtually overnight - 18" snows in May? "Is this the new normal?" Time will tell, but researchers increasingly see a link with recent melting in the Arctic. If you've seen the documentary film "Chasing Ice" you know what I'm referring to: 1.3 million square miles of ice lost in 30 years. Warming at the top of the world may be reducing temperature contrasts, turning the jet stream into a "sluggish estuary", according to Rutgers researcher Jennifer Francis.

What does this mean to us? It means that we shouldn't be surprised to see more severe weather that lasts for longer durations. Our weather can be expected to whiplash from one extreme to another. In the U.S. we are seeing some evidence of this. Alternating wet, snowy winters and warm non-winters. Summers of either extreme heat and drought – or unbelievable flooding. But don't just take my word for it. A leading researcher in this area, Dr. Jennifer Francis says,

"The Arctic is warming two-to-three times faster than the rest of the northern hemisphere -- the loss of sea ice, spring snow cover, increased Greenland melting, and permafrost degradation are all symptoms of and contributors to this warming. It's inconceivable that a change of this scale and magnitude will not have substantial impacts on the atmosphere, ocean, and land both within the Arctic and also beyond the Arctic where millions of people live. These impacts will affect not only the physical system -- such as weather patterns and ocean circulation -- but also life on land and in the ocean. Exactly how these effects play out is a wide-open topic of research..."