It’s hot in the United States! This picture from the NOAA Environmental Visualization Laboratory shows the temperature at 5 pm Eastern Time on the 12th of July:
Half the population is suffering under ‘heat advisories’. These kick in when the heat index—a measure of perceived temperature that takes humidity into account—surpasses 105°F (about 40 °C), or when the nighttime low exceeds 80°F (about 27 °C) for two consecutive nights.
Here’s what the Capital Weather Gang has to say:
East of the continental divide, it’s difficult to escape today’s searing heat. NOAA reported that as of 1 p.m., heat advisories or excessive heat warnings affected 150 million Americans in 23 states. Washington, D.C. had been under a heat advisory earlier today, but it was canceled when it became clear temperatures would fall just below advisory criteria.
Almost all of the south central and southeast states have seen heat indices exceed 105 degrees Tuesday afternoon. Some sample readings at 3 p.m.: Little Rock 109, St. Louis 109, Raleigh 105, Memphis 111, Charleston 108.
In recent days, the searing heat has set scores of new record high temperatures across the eastern two thirds of the country. Yesterday alone, 41 record highs were set including Ft. Smith, Ar. (107), Indianapolis, In. (96), Louisville, Ky. (97), Watertown, Ny. (90), Altoona, Pa. (94), and Charleston, WV (95).
Record high minimum temperatures have been more even pervasive, offering little nighttime relief from the oppressive afternoon heat. On Monday, 132 record high lows were set.
In Louisville, Kentucky this morning, the low dropped to a mere 84 degrees. Meteorologist Eric Fisher at The Weather Channel tweeted: “That. Is. Filthy. Heat Index was still above 100 at 5am.”
Some of the most remarkable heat occurred on in central Plains on July 9 and 10. Oklahoma City reached 110 degrees on the 9th, tying its all-time high for the month. Wichita, Kansas rose to 111 degrees on the 10th, its hottest temperature in 30 years. See CapitalClimate for more on the records which extended into Arkansas and Missouri.
In both Oklahoma City (13 days) and Dallas (10 days), the mercury has reached 100 or better for at least ten straight days. Hot weather is predicted to persist there through the weekend, at least.
Across the country during the month of July, record highs have outnumbered record lows 349 to 68 (or more than 5:1).
Could any of this be related to, umm, global warming? Joe Romm has a blistering critique of the American media’s failure to mention this possibility:
• Joe Romm, After Story on Monster Heat Wave, NBC Asks “What Explains This?” The Answer: “We’re Stuck in a Summer Pattern”!, Climate Progress, 13 July 2011.
Inference is a tricky business. It’s easy to spot patterns where they don’t exist, especially when the patterns are as subtle as an increase in extreme weather events, also known as ‘global weirding’. If there’s a flood, or a drought, we can easily explain it this way. The human mind, after all, is programmed to seek out patterns: we can see faces in clouds.
But it’s also easy to fail to recognize patterns where they do exist—especially when acknowledging them would require difficult changes in behavior. “Am I an alcoholic? No, I just got really drunk last night… and, okay, the night before…”
Earlier this spring, Bill McKibben had a sarcastic editorial about this:
• Bill McKibben, A link between climate change and Joplin tornadoes? Never!, Washington Post, 24 May 2011.
It starts:
Caution: It is vitally important not to make connections. When you see pictures of rubble like this week’s shots from Joplin, Mo., you should not wonder: Is this somehow related to the tornado outbreak three weeks ago in Tuscaloosa, Ala., or the enormous outbreak a couple of weeks before that (which, together, comprised the most active April for tornadoes in U.S. history). No, that doesn’t mean a thing.
It is far better to think of these as isolated, unpredictable, discrete events. It is not advisable to try to connect them in your mind with, say, the fires burning across Texas — fires that have burned more of America at this point this year than any wildfires have in previous years. Texas, and adjoining parts of Oklahoma and New Mexico, are drier than they’ve ever been — the drought is worse than that of the Dust Bowl. But do not wonder if they’re somehow connected.
If you did wonder, you see, you would also have to wonder about whether this year’s record snowfalls and rainfalls across the Midwest — resulting in record flooding along the Mississippi — could somehow be related. And then you might find your thoughts wandering to, oh, global warming, and to the fact that climatologists have been predicting for years that as we flood the atmosphere with carbon we will also start both drying and flooding the planet, since warm air holds more water vapor than cold air.
It’s far smarter to repeat to yourself the comforting mantra that no single weather event can ever be directly tied to climate change. There have been tornadoes before, and floods — that’s the important thing. Just be careful to make sure you don’t let yourself wonder why all these record-breaking events are happening in such proximity — that is, why there have been unprecedented megafloods in Australia, New Zealand and Pakistan in the past year. Why it’s just now that the Arctic has melted for the first time in thousands of years. No, better to focus on the immediate casualties, watch the videotape from the store cameras as the shelves are blown over. Look at the news anchorman standing in his waders in the rising river as the water approaches his chest.
Luckily, scientists are busy at work on these questions. For example, these papers on floods came out in February:
• Pardeep Pall, Tolu Aina, Dáithí Stone, Peter Stott, Toru Nozawa, Arno Hilberts, Dag Lohmann, and Myles Allen, Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000, Nature 470 (17 February 2011), 382–385. Supplementary information available for free online.
• Seung-Ki Min, Xuebin Zhang, Francis W. Zwiers and Gabriele C. Hegerl, Human contribution to more-intense precipitation extremes, Nature 470 (17 February 2011), 378-381.
I believe that someday we will understand whether and how extreme weather events are linked to global warming—if not individually, at least statistically. Whether we’ll understand it soon enough for it to make much difference—I’m less sure about that.
Luckily, I’m back in Singapore now, so I don’t personally have to worry about the heat wave in the USA. No heat advisory here! The weather is quite normal, with the heat index a nice cool 100 °F (or 38 °C).
I remember growing up in Kansas about 40 years ago when it was normal to have three-week-long stretches of lows at 3am of 90F or over, and the highs were such that cars’ tires sank into the asphalt, leaving tread marks, and if you put too much air in your bike tires, they’d blow right off of the rims if left out in the sun.
Needless to say, one needs to do statistics to tell if it’s really getting warmer or not. Here’s some non-statistical information about heat in Kansas:
• Roxana Hegeman, Hutchinson nation’s hot spot at 112 amid Kansas heat wave, The Associated Press, 11 July 2011.
For the non-Americans, 112 °F is 44.4444… °C.
I’ve read in the news that the insurance company for insurance companies, the reinsurance company Münchner Rück, has had the worst year of its entire history. It would be necessary to try to find out which part of their problem is due to an increase of insurable assets in the world, and which part is due to an increase of natural disasters. I don’t know. But I trust their numbers more than I trust the numbers of any NGO or government agency. If they say they are losing money on a big scale, they really do, that’s for sure.
It would be very difficult to separate out the effect you wanted. You’d need to exclude non-climatic natural disasters, like the Japanese Earthquake, and non-climatic human disasters, like the Gulf spill. And then you’d need to control for schemes which inflate insurance costs. In the UK, we have companies which specialise in acquiring payment of thousands of pounds for anyone involved in a road accident, however minor the impact. Not hard to believe this could happen in property claims.
Even with climatic disasters like flooding, you’d have to know if changes in practice made them worse, like building in flood plains.
Munich Re should be able to sort out these things. A decent insurance company depends on this. From a press release Sept. 2010:
In our earlier discussion about Adapting to a Hotter Earth, I quoted Munich Re, one of the world’s largest reinsurers. (Are they the same as Münchner Rück?)
In September 2010, they wrote:
I also mentioned that Dr. Peter Hoeppe, head of the Geo Risks Research Department at Munich Re, wrote:
In response to this, srp argued that:
Surely someone has tried to sort this out? It’s important!
How do you count these events? Does the recent Japanese earthquake count as 1? Is a large aftershock part of the same event? Is a single tornado an event or is it part of a storm? How many events make up recent Mississippi flooding?
I still think you’d be better off analysing metereological data than insurance data. When people have to find new building plots in crowded places they end up putting up houses in daft places. In the UK we have new housing which insurers won’t touch. There are also subtle shifts in farming practices over the years, loss of marshland, failure to clear ditches, livestock compacting the soil, which can affect local flooding. Then there are shifts in river dredging practices, not always helpful flood ‘defences’, etc. If you want to know about climate change, why not use meteorological instruments?
Yes, attributing causes is tricky. Seeing that blocking events seem to be involved in so many floods, droughts, heatwaves and freezes, e.g., this account of the Russian heatwave, maybe a global measure of ‘blockedness’ would be useful.
Interesting! Maybe this ‘blocking’ effect is what the meteorologist ridiculed by Joe Romm was referring to:
To a naive eye, this sounds a bit like the old explanation of why opium puts people to sleep: because it has a ‘dormitive power’. But maybe there’s something to it… which might be explained by a general theory of ‘blocking’.
(By the way, note that the year 1936 has come up twice in these comments.)
Up to now, blocking events look entirely natural and not linked to CO2 rise. More on the Russian heat wave of 2010 from NOAA:
and New Scientist says
— But climate models also fail at predicting the rapid decay of Arctic sea ice. That will obviously have a great influence on weather patterns (cold surface gone, more warmth absorbed) – perhaps also on blocking events. We need to wait and see the statistics coming in over the years.
—
That current global warming (soon heating) has an influence on extreme weather is almost a no-brainer. When folks wonder I use to tell them it’s just steam engine physics and elementary statistics: Warmer air holds more moisture, transporting more of it away from some places (drought, e.g. Russian soil 2010) and/or dumping more of it in other places (flood, e.g. Pakistan 2010). AFAIK it’s currently just 4% more, but there’s the miracles of the Gaussian distribtion: Tweak its parameters a little bit and you get large changes at the extreme ends – voila, here come the black swans (This page has a nice image.)
Just out of curiosity, how does the temperature anomaly correlate with disbelief in the scientific consensus?
I don’t know, but there’s some correlation with the prevalence of AIDS. Here’s the heat map:
and here’s a newly released interactive map showing the number of people living with a diagnosis of AIDS in 2008:
Correlation does not imply causation.
The AIDS map looks an awful lot like a population density map.
You scared me for a second there, since I read incoming comments in my email, so I saw yours without that map in front of me.
Just in case anyone else is similarly scared: the AIDS map doesn’t show AIDS cases per square kilometer (which would be idiotic, and obviously correlated with population density), but the fraction of people who have AIDS. So, Blake is suggesting that the chance of a person having AIDS is positively correlated to the population density… which makes some sense, since you have to actually meet someone to get AIDS.
It would be very interesting to see how much of the variations in AIDS infection can be explained by this simple fact. Unsurprisingly, the conclusions that made the news are more politically charged:
By the way, for non-English speakers out there: I would never say ‘conduct a report’. You can conduct a study and then write a report. (Sorry, I’m an editor’s son.)
[…] Rainbow frog! Robotic mouth! Heat wave*! […]
I find that data on climate change is hard to come by and it seems different organizations have different numbers. For instance, weather.gov, which is the national weather service, states that between 1999 and 2003 only 1029 people succumbed to heat related deaths. This is in contrast to CDC.gov, the center for disease control, which lists 3442 deaths, a factor of 3 different. It’s hard to know the motives for under or over reporting.
Interesting. I know a bit more about how to find data on temperature, rainfall etc. than how to find data on deaths due to heat.
I imagine there’s quite a bit of room for different definitions of ‘heat related deaths’. In a different direction, I’ve heard that heavy snowfalls in the US cause a lot of heart attacks among people shovelling their driveways. If you die that way, is it a ‘cold-related death’? Similarly, deaths in the US due to traffic accidents after rainstorms greatly exceed deaths more directly caused by hurricanes and tornadoes.
The heat wave has gotten worse from 13 July to 21 July: see the animated movie from NOAA, and it’s not predicted to let up very soon:
This picture is from Weather Underground. Note that this graphic shows the predicted ‘heat index’, computed from the temperature and humidity.
On Weather Underground, a professor at U. Michigan named Ricky Rood is writing a series of articles about the heat wave in the US and climate change. As David Corfield suggested, “persistence” of high pressure systems is important. And Rood says it’s more likely with high sea surface temperatures.
Rood writes:
This article:
• Jason Samenow, Spring extreme weather events in 2011 in U.S.: historic and record setting, Capital Weather Gang, Washington Post, 16 June 2011.
lists some of the shocking events that have been happening this year in the USA. This list ends in June, so it does not include the current heat wave:
Shocking? But is it shocking enough as teachable moment for the U.S.?
Yeah, it’s impressive – but standard business around the planet for some years meanwhile. E.g. the U.S. hasn’t yet had the really ugly forest fires like Russia or Australia. Or super floods like Pakistan or Australia. Hey, Australia seems already have learnt a little?