Blog: Climate Dice- The Fourth Roll: Lottery Numbers For Winter 2011/2012
How well did that prediction of a "mild" winter work out?
The National Climatic Data Center has finished processing the rankings for December, January and February, which are considered meteorological/climatological winter in the Northern Hemisphere for 2011/2012 for the lower 48 states. So, for everyone who participated in my second lottery contest, the numbers were: 85/115/102 with an overall "power-ball" ranking for the season of 114. Just like summer and fall 2011 not even one month was below average.
The winner was Buzz Bernard, who came closest to picking the correct numbers. He posted his numbers before the deadline on January 1st....not bad Buzz....your picks were 104/100/75 for DEC/JAN/FEB 2012.
Incidentally, the "Mega-Ball", or yearly, number or ranking for the lower 48 states in 2011 was 95, which was very similar to that of 2010 (92 out of a possible warmest 117). Rankings began in 1895. The last couple of years have been warm across the United States.
So were those of us who predicted a mild winter just "lucky", or are those lottery picks weighted toward high numbers due to climate change? Let's play the Climate Lottery for spring to see if the Climate Dice will come up warm again across the U.S. Just like last time pick three numbers between 1 and 118 (with one representing the coldest possible ranking and 118 being the highest possible ranking) for MAR/APR/MAY 2012. Also pick a "Power Ball" or overall ranking number for spring 2012 between 1 and 118. Please give your picks in the reply section to this blog by April 1st. I'll announce another winner shortly after the National Climatic Data Center processes averages on my next post around June 10th. My forecast is for spring to be closer to average than this very mild winter but remaining, overall, above long term averages for the entire season. I'm waiting for the pattern to reverse for a month or more in association with the Arctic Oscillation...there will be more information about that phenomenon later in this post when I break down how the Climate Lottery numbers verified this winter. Also we are "due" to see at least one below average month during the spring. I won't be shocked, at all though, if just like summer, fall, and winter not one single month of spring is below average. There are indications that March will be warm. We will all have a fairly good idea where March will rank by April 1st, so as usual, the quick pick for the first month will be an educated freebie. Ominously enough, a tornado outbreak in association with an anomalously warm pattern in the eastern U.S. has already occurred during the first week of March.
For reference the following are links to my first three posts:
http://www.weather.com/blog/weather/8_26102.html?from=blog_permalink_mainindex
http://www.weather.com/blog/weather/8_25602.html?from=blog_permalink_mainindex
http://www.weather.com/blog/weather/8_23192.html?from=blog_permalink_month
Well, I couldn't resist playing the Climate Lottery, so at the last minute I put in some picks, which were: 106/94/68 for DEC/JAN/FEB 2011/2012 with an overall "Power Ball" or seasonal pick of 99. Once again, the season, as a whole, was above long term averages with no individual month below average; and thus, having above average rankings. I'll reiterate once more that due to climate change it is unlikely for a land area the size of the contiguous United States to have below average temperatures for an entire season. I'm not going to state that there will NEVER AGAIN be another cold season for the United States, but due to man induced global warming, the chances for an entire season of below average conditions is becoming much less likely. As stated in my third post, only an increase in volcanic activity from what is presently occurring at the moment can significantly slow the overall warming trend of the planet. What happened over the winter is more proof of the climate dice being loaded for warmth in the United States.
The reader may site, however, that the Northern Hemisphere did see some below average conditions during the winter...most notably in Alaska and Europe. Some climate scientists do have explanations for why Europe has seen some very cold winters the last few years. Europe's current cold winter pattern fit well with the latest thinking in association with climate change.
"The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming," said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. "The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favors the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe."
Here's a breakdown of the National Climatic Center's ranking numbers for each month of the winter:
In December the overall ranking for the lower 48 states was 84 (out of 117):
Some of you were a little confused about how NCDC comes up with the overall rankings for the lower 48 states.The ranking for the U.S., as a whole, is not an average of the rankings for each individual state. Rather, the ranking is a comparison of the average temperatures of the entire continental U.S. for the last 117 years through 2011.
Initially, winter got off to a cold start with a frigid air mass diving southward through the West. I did not take into account the first 10 days of the month in the West; thus, I overestimated how warm the overall ranking for the month would be. The rest of December was very mild for most of the country. Some of the Northeast states had their second or third warmest Decembers in recorded history.
So why was the winter, for the most part, very mild? Remember what I referred to in my last post...the positive North Atlantic or Arctic Oscillation. This feature has remained basically intact from the Hudson Bay into Greenland all winter long. Charts from the National Ocean and Atmospheric Administration depict what has happened in association with the NAO over the last year. Charts can be found at this link: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif
Notice that the graphs on the charts are primarily above 0 indicating that the NAO was in a positive phase.Climatologists have found that during the cold season when the Arctic Oscillation is in mostly a positive phase combined with global warming; most of North America will see a mild winter. Waa-la that is what happened this season. What was somewhat surprising was the persistence of the positive Atlantic Oscillation over the entire season. Usually, if this mild pattern occurs during the winter, there are a few weeks when the pattern becomes negative, but that was not the case during the winter of 2011/2012.
Not all of North America was above average, however. Alaska saw some of the coldest conditions for that state's history into January. Due to the nature of weather patterns, some areas of the planet will see below average periods; thus, fooling contrarians, but over periods of a season or longer, warmer than average conditions will appear for those same locations in the climate record.
In January the overall ranking for the lower 48 states was 115 (out of 118).
January was startlingly mild, just as July and August 2011 were alarmingly hot. January 2012 was the 4th warmest January for the lower 48 states in recorded history. The northern Plains was particularly mild where there was well below average snow cover and over 1250 daily record highs were either tied or set. The climate dice came up very red in December. My "quick pick" for January of 94 was 11 points too low.
Many people across the United States were asking what had happened to winter. The following is a cute cartoon that I will attribute to Nate Johnson that basically sums up what some meteorologists have been thinking about this season:
Despite the warm January, there was some winter weather. A storm officially dumped seven inches of snow on Seattle during the middle of the month, for instance. All kidding aside though, the winter weather across the United States is probably a precursor of very mild seasons in the future looking at climate trends. I would expect that in the next couple of decades though, there will be wild fluctuations of mild patterns most years with a few more colder and snowier winters depending mostly on what happens with the Arctic Oscillation.
In February the overall ranking for the lower 48 states was 101 (out of 118).
The overall ranking for boreal winter 2011/2012 was 114 (out of 117).
The weather pattern that produced the mild weather in February was similar to that of January. The pattern did shift slightly, however, such that the Northeast was particularly warm. Massachusetts had its warmest February in recorded history.
The "Power Ball" number for the entire U.S. was 114 (out of 117), so the lower 48 states ended up having the 4th warmest winter in recorded history (since 1895). Think about this for a moment: What are the chances in a regular lottery of picking a number from 1 to 117 as high as 114? Again, due to climate change, I think that the game is rigged towards warmth.
I am getting all of my ranking numbers from the National Climatic Data Center.
The link for the National Climatic Data Center's Climate at a Glance Site where the rankings are archived is: http://www.ncdc.noaa.gov/oa/climate/research/cag3/cag3.html
I'm keeping the format on all of my charts the same as on the last two posts.The average ranking for 2012 is 59 since the coldest ranking would be 1 and the hottest would be 118. I have color coded all rankings below 49 blue and all those above 69 red with rankings + or -- 10 from the median value of 59 black.
The following are the rankings so far for the 2010's:
Also, for reference, the following are "Power-Ball" and "Mega-Ball" ranking numbers from 1960 to the present. I did not chart seasonal ranking numbers on my last couple of blogs, but will this time. For the sake of discussion I'll define Mega-Ball numbers as NCDC rankings for each year and Power-Ball numbers as NCDC rankings for each season. Seasonal or Power-Ball rankings for winter are those for DEC/JAN/FEB, spring are those for MAR/APR/MAY, summer is JUN/JUL/AUG, and fall is SEP/OCT/NOV. Winter rankings obviously will overlap from one year to the next, but for convenience, the National Climatic Data Center will infer that winter 2012 was for DEC 2011, JAN 2012 and FEB 2012, for example. Also, keep in mind that NCDC rankings for seasons compare temperature averages for individual seasons and are not merely an average of rankings of individual months of a season or year.
Even though two out of the three of the winter months occurred in 2012, the ranking for winter 2011/2012 was the 117th. Rankings from NCDC start in January 1895. The first full winter that could be ranked did not occur until the data for DEC 1895, JAN 1896 and FEB 1896 were complete ...that's why DEC 2011, JAN 2012 and FEB 2012 would be the 117th winter to be ranked, not the 118th.
Notice that since the start of 2000 only four out of forty-nine seasons have been below average or "blue". Thirty-nine out of the forty-nine seasons since 2000 have been "red" or above average. Indeed, the climate dice are very much loaded for above average temperatures for the lower 48 states looking at recent history.
Well, that's it for this post. I just hope that spring 2012 is not as volatile as that of 2011 despite this first horrendous outbreak of tornadoes this week.
Guy Walton
Lead Forecaster, The Weather Channel
