SDF: Tropical Spring Heatwave
Editor’s Note: It’s Science Ditty Friday. Every Friday REALscience compiles a song (generally with an accompanying video) to kick your weekend off with a musical start. Have a favorite science song? Send it to firstname.lastname@example.org.
Spring has barely sprung and already much of the country is experiencing abnormally high temperatures. Trees are budding a month early and over 7,000 March high temperature records have been broken. Across the Northeast and Midwest winter has suddenly turned into summer.Lake Michigan is as warm now as it normally is in June. A balmy 78-degree day in Chicago had people talking, including President Barack Obama who says he’s “a little nervous” about global warming. The President said, “It’s warm every place. It gets you a little nervous about what’s happening to global temperatures. But when it’s 75 degrees in Chicago in the beginning of March it gets you thinking.” At a campaign fundraiser with Oprah Winfrey, the TV network owner said, “Something’s wrong.”
Instead of temperatures hovering in the mid-40s for early March, the windy city has been enjoying an unseasonably warm streak of 80-degree days, including reaching 87 degrees March 21. Chicago rarely reaches the 80-degree mark in April, let alone March.
International Falls, Minnesota saw a 93-degree temperature swing from -14 to 79 from March 9-18. Marquette, Michigan obliterated its old March 21 record high of 49, replacing it with a new record of 81. Even the low temperatures that day was higher than the old record high.
Those staggering numbers have meterologists across the heartland using words like “freak heatwave,” “record heat wave.” And Popular Science says it’s “almost like science fiction.”
University of Edinburgh climate scientist Gabi Hegerl sees evidence that extreme heat events like the one that began in a good chunk of the U.S. on March 12 have become more common and more severe, including at the regional level in parts of the U.S. She says, “This is consistent with observing more and stronger heat waves.”
And she is not alone. A group of climate scientists are studying the role that climate change plays in individual extreme weather events. They are pioneering a new scientific discipline called climate attribution. And they agree that global warming has made March’s summer-like temperatures more likely but they say that natural variability also played a vital role.Since the climate is a very complex system it is difficult to pinpoint exact cause and effect relationships without careful study. And while the current bout of heat is still ongoing (but likely to peter out over the weekend) scientists plan to look at it carefully over the next few months.
Hegerl suggests conducting climate model studies where scientists compare the odds of this event occurring with and without added greenhouse gases in the atmosphere, such as carbon dioxide, “to see how much the warming has changed the odds.”
Scientific studies of previous heat waves using this probability-based approach have shown that global warming is increasing the odds of heat extremes. But to what extent is unclear.
Both global-warming trends and shifts in atmospheric circulation are help make an extreme weather event, so scientists need to observe the whole climate system in order to investigate how often an event with these extreme characteristics takes place under the two alternative scenarios.
A study published in the October issue of the Journal Proceedings of the National Academy of Sciences found a local warming trend in the Moscow, Russia area is quintupling the number of heat records there per decade. The study also concluded that there is an 80 percent chance that the 2010 July monthly heat record in Russia wouldn’t have happened without global warming.
A similar study after the European heat wave in 2003 reached the same conclusion.
NOAA deputy research director Randall M. Dole says the U.S. spring heat wave is “absolutely” global warming. He says, “The planet as a whole is warming, the continents on average are warming faster than the oceans, so there is a great body of scientific evidence that would support such an interpretation. The question is how much.”
The Moscow heat wave study suggests that global warming enables extreme heat events, increasing the frequency of such weather anomalies but not causing them directly or being responsible for one extreme event characteristic.
Dr. Dole says that climate change definitely stacked the deck in favor of this springtime heat wave but global warming’s small role just doesn’t explain its intensity.That he attributes that to a massive ridge of high pressure in the Jet Stream that is blocking weather systems from much of the country and he thinks the lack of snowpack also played a role. With less snow than average (thanks to a warm winter) sunlight doesn’t bounce as much energy off a white ground or keep the air temperatures near the ground cooler.
The high pressure dome that is blocking storms from reaching the midsection of the U.S. and Canada are similar to those that influenced the Moscow heat wave in 2010 and the European heat wave in 2003.
Scientists don’t yet understand what causes these big high pressure systems that block incoming weather systems and they don’t yet grasp what effects climate change are having on the frequency and intensity of those patterns.
Martin Hoerling agrees with Dole that climate change didn’t play a leading role in this spring heat wave. He says, “Meteorology, not climate change, is the main ingredient in the current March 2011 U.S. extreme warmth.”
Climate scientist Kevin Trenberth says, “Indeed [greenhouse gas-driven] warming is not dominant, but I suspect when all the evidence is in we will find that the event likely would not have occurred without global warming.” He adds, “The odds will be so low.”
But this burst of springtime summer is about to end. The high pressure system is breaking down already and a wet weekend is on the way thanks to a low pressure system that will push out the high.
Well-known global warming advocate Bill McKibben summed up the heat wave on Twitter saying, “I know I’m a little obsessed with this heat wave–but: it’s not just off the charts, it’s off the wall the charts are tacked to.”
The Capital Weather Gang at the Washington Post says, “Meteorologists and other weather commentators have frequently commented they’ve never seen anything like this, exhausting superlatives.”
Here’s a round-up of the popular words weather forecasters have used to describe Spring Heat Wave 2012: Mind-boggling, eye-popping, unthinkable, unreal, unbelievable, astonishing, unfathomable, historic, unprecedented, crazy, insane, mutant, incredible, amazing, stunning, unheard of, surreal, remarkable, jaw-dropping.
When low temperatures are the same as previous record highs, the deputy director of the National Oceanic and Atmospheric Administration’s Climate Prediction Center calls that “incredible.” Mike Halpert says,”To me, that’s just mind-boggling.”
By: Marilyn Monroe
Oh! We’re having a heatwave, a tropical heatwave
The temperature’s rising, it isn’t surprising,
she certainly can can-can
She started a heatwave by letting her seat wave,
in such a way that the customers say
that she certainly can can-can
Gee,gee! Her anatomy makes the mercury rise to 93!
Having a heatwave, a tropical heatwave, the way that she moves,
that thermometer grooves that she certainly can…
(What’s your name honey? Pablo). Certainly can..
(Chico, Miguelito, Pablo, Chico, Miguelito)…oh, can-can.
Pablo, it’s saying here in the weather report,
it’s saying a fairly warm air is moving in from..(Where?) Jamaica
Moderately high air pressure will cover the NE and.. (where else?)
The Deep South. Small danger of (what?) Fruit frost!
Hot and humid nights can be expected.
Vincent 95, Guadeloupe 97, Santo Domingo 99. Pardon me? 105?
We’re having a heatwave, a tropical heatwave,
the temperature’s rising, it isn’t surprising,
I certainly can can-can
I started this heatwave in such a way
that the customers say that I certainly can can-can
The man who need makes the mercury rise to 93
We’re having a heatwave, a tropical, a tropical heatwave
the way that I move, that thermometer grooves
She certainly certainly certainly can
I certainly certainly certainly can can-can
Written by Irving Berlin
Performed by Marilyn Monroe
(c) 1954 There’s No Business Like Show Business