Northeast hit by record global-warming-type deluge
U.S. media misses the story, while "China spends big to counter severe weather caused by climate change"
March 31, 2010
It’s pretty remarkable that we are having record rainfall and record flooding in the cold season month of March. It’s much easier to set records in August, when there is much more moisture in the air available for record rains.
The Northeast has been walloped with record-smashing deluges and flooding.
I have called this type of rapid deluge, “global warming type” record rainfall, since it is one of the most basic predictions of climate science — and it’s an impact that has already been documented to have started, as I’ll discuss.
Of course, in this country, you’ll be hard pressed to find any discussion of global climate change in connection with this deluge. The Today Show ran 3 stories this morning and never mentioned climate change at all. But is it too much to ask after so many in the media mislead the public into thinking that the record snow was somehow evidence against human-caused global warming?
Other countries don’t have a problem explaining to the public that extreme weather is already becoming common, just as scientists said it would (see “Must re-read statement from UK’s Royal Society and Met Office on the connection between global warming and extreme weather“). Indeed, at the very same time all the U.S. records were being smashed, the UK’s Guardian reported that China is taking action to deal with warming-driven extreme weather:
China will tomorrow start ramping up preparations for typhoons, dust storms and other extreme weather disasters as part of a 10-year plan to predict and prevent the worst impacts of climate change….
China has a long history of devastating floods and droughts, but officials said the problems were intensifying.
“It is necessary to respond to the new situation under climate change to avoid and mitigate the losses caused by meteorological disasters,” said Gao Fengtao, deputy director of the state council’s legislative affairs office, as he unveiled the new policy.
In recent years, he said, disasters were characterised by “sudden occurrence, wider variety, greater intensity and higher frequency in the context of global warming”.
But in this country, as I’ve noted many times, the anti-science disinformers try to shout down any talk of a link between climate change and extreme weather.
Nonetheless, the great Nor’easter of 2010 would appear to easily qualify as a global-warming-type deluge. As uber-meteorologist Jeff Masters noted in his post (quoted above), perhaps remarkably, it has occurred during March, when you wouldn’t normally expect such records to be set. Stu Ostro, Senior Meteorologist at the Weather Channel, made a comparable point about Georgia’s devastating September rainstorms. Of course, Ostro pointed out there was no way to know if global warming had “caused” the record floods, but
Nevertheless, there’s a straightforward connection in the way the changing climate “set the table” for what happened this September in Atlanta and elsewhere. It behooves us to understand not only theoretical expected increases in heavy precipitation (via relatively slow/linear changes in temperatures, evaporation, and atmospheric moisture) but also how changing circulation patterns are already squeezing out that moisture in extreme doses and affecting weather in other ways.
That’s why I use the term global-warming-type deluge — but only when a changing climate “set the table” for something that truly smashes through the record books.
Another remarkable feature of the storm was explained by Steve Scolnik of Capital Climate in his post, which lists all of the major records that were broken:
The NWS [National Weather Service] notes that this is now the 3rd episode of excessive rainfall in the region within the last 3 weeks, an unprecedented occurrence in recorded history.
In Providence, RI, yesterday’s rainfall total of 3.47? nearly tripled the previous March 29 daily record of 1.19? set in 1931. The 4.31? measured so far today also smashes the old daily record of 2.57?.
Note: In the AP photo at the top, an oil slick runs through the Pawtuxet River in Warwick, RI.
Jeff Masters has more of the records:
Record rains from a slow-moving and extremely wet Nor’easter have triggered historic flooding in Rhode Island and Southeastern Massachusetts, with several rivers exceeding their 100-year flood levels. The 16.32? of rain that has fallen on Providence, Rhode Island, this month is the most rain recorded in any month, besting the previous record of 15.38? set in October 2005. Blue Hill Observatory in SE Massachusetts also set a record for wettest month ever, with 18.79? (previous record: 18.78?, August 1955.) Records extend back to 1905 and 1885 at the two sites. The Rhode Island all-time state record for heaviest precipitation in a month was smashed as well, thanks to the 19.62? observed this March at North Kingstown. The old state record was 16.70?, set at North Foster in October 2005. Many locations in the Northeast recorded their wettest March ever, including New York City and Boston.
This was not one-day weather event over a small area. This was a month-long regional event of staggering proportion. Masters has a figure of “observed precipitation for the month of March” courtesy of NOAA:
How does one talk about this? NPR ran a good interview with Dr. Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research, back in February on the snowstorms (see “President Obama explains the science behind climate change and extreme weather“):
Mr. KEVIN TRENBERTH (Scientist, National Center for Atmospheric Research): The fact that the oceans are warmer now than they were, say, 30 years ago, means there’s about, on average, 4 percent more water vapor lurking around over the oceans than there was, say, in the 1970s.
JOYCE: Warmer water means more water vapor rises up into the air. And what goes up, must come down.
Mr. TRENBERTH: So one of the consequences of a warming ocean near a coastline like the East Coast and Washington, D.C., for instance, is that you can get dumped on with more snow, partly as a consequence of global warming.
Or, when it is warm enough, you get dumped on with more rain, partly as a consequence of global warming. And it is getting warm (see ” Global cooling bites the dust: Hottest January followed by second hottest February. Now March is busting out“).
For completeness’ sake, I’ll quickly run through some of the literature. Regular readers can skip the rest of this post. You can find more here and there’s some terrific technical meteorological analysis here.
In 2004, the Journal of Hydrometeorology published an analysis by NOAA’s National Climatic Data Center that found “Over the contiguous United States, precipitation, temperature, streamflow, and heavy and very heavy precipitation have increased during the twentieth century.”
They found (here) that over the course of the 20th century, the “Cold season (October through April),” saw a 16% increase in “heavy” precipitation events (roughly greater than 2 inches [when it comes as rain] in one day), and a 25% increase in “very heavy” precipitation events (roughly greater than 4 inches in one day)– and a 36% rise in “extreme” precipitation events (those in the 99.9% percentile — 1 in 1000 events). This rise in extreme precipitation is precisely what is predicted by global warming models in the scientific literature.
In fact, the last few decades have seen rising extreme precipitation over the United States in the historical record, according to NCDC’s Climate Extremes Index (CEI):
An increasing trend in the area experiencing much above-normal proportion of heavy daily precipitation is observed from about 1950 to the present.
UPDATE: Here is a plot of the percentage of this country (times two) with much greater than normal proportion of precipitation derived from extreme 1-day precipitation events (where extreme equals the highest tenth percentile of deluges, from NOAA):
No surprise, then, that as a recent WWF post noted, U.S. Sees Wettest October on Record; Arkansas Records are Washed Away.
Even the Bush Administration in its must-read U.S. Climate Change Science Program report, Weather and Climate Extremes in a Changing Climate, acknowledged:
Many extremes and their associated impacts are now changing…. Heavy downpours have become more frequent and intense….
It is well established through formal attribution studies that the global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases.… The increase in heavy precipitation events is associated with an increase in water vapor, and the latter has been attributed to human-induced warming.
In the future, with continued global warming, heat waves and heavy downpours are very likely to further increase in frequency and intensity. Substantial areas of North America are likely to have more frequent droughts of greater severity.
In short, get used to it.
And remember, this is all from about a 1°F warming in the last few decades. We are on track to see nearly 10 times that over much of the United States on our current emissions path (see “Our hellish future: Definitive NOAA-led report on U.S. climate impacts warns of scorching 9 to 11°F warming over most of inland U.S. by 2090 with Kansas above 90°F some 120 days a year — and that isn’t the worst case, it’s business as usual!”
In short, we ain’t seen nothing yet.
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