Two seminal Nature papers join growing body of evidence that human emissions fuel extreme weather, flooding that harm humans and the environment

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"Two seminal Nature papers join growing body of evidence that human emissions fuel extreme weather, flooding that harm humans and the environment"

Here we show that human-induced increases in greenhouse gases have contributed to the observed intensification of heavy precipitation events found over approximately two-thirds of data-covered parts of Northern Hemisphere land areas. These results are based on a comparison of observed and multi-model simulated changes in extreme precipitation over the latter half of the twentieth century analysed with an optimal fingerprinting technique.

Changes in extreme precipitation projected by models, and thus the impacts of future changes in extreme precipitation, may be underestimated because models seem to underestimate the observed increase in heavy precipitation with warming

That’s from the first of two seminal studies in Nature, “Human contribution to more-intense precipitation extremes” (subs. req’d).  The second looked at “Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000” (subs. req’d):

Occurring during the wettest autumn in England and Wales since records began in 1766 these floods damaged nearly 10,000 properties across that region, disrupted services severely, and caused insured losses estimated at £1.3 billion….

Here we present a multi-step, physically based ‘probabilistic event attribution’ framework showing that it is very likely that global anthropogenic greenhouse gas emissions substantially increased the risk of flood occurrence in England and Wales in autumn 2000.

in nine out of ten cases our model results indicate that twentieth-century anthropogenic greenhouse gas emissions increased the risk of floods occurring in England and Wales in autumn 2000 by more than 20%, and in two out of three cases by more than 90%.

Scientists have predicted for decades that human-caused global warming would increased extreme weather events that cause severe harm to humans, property, and the environment.  These two studies are but the latest in a growing body of scientific literature demonstrating that these predictions are coming true now.

They should help lay to rest the myth that human-caused global warming will contribute to grievous harm only in some far-off future.  They also strongly support the view that the human-induced increases in greenhouse gases have contributed to the devastating extreme events that hit Australia and other parts of the world in the past several months, helping to drive up food prices (see how extreme weather, climate change drive record food prices).

The NYT has a great headline on this story, “Research Links Heavy Rains and Snow to Humans.”  It is all heavy precipitation that humans are intensifying.

Of course, many of our top climate scientists have been documenting and explaining these types of conclusions for a while.   I’ll list a bunch of the papers below.  Kevin Trenberth, head of NCAR’s Climate Analysis Section, has a new paper out, “Changes in precipitation with climate change” that is well worth reading.  So I asked him for a comment on these two studies.  He told me:

These studies are very reasonable, and the main mechanism is well understood: it relates to the increased moisture in the atmosphere with higher temperatures and warmer oceans.   However, the studies may well be conservative as the tools available (the climate models), do not simulate precipitation and all of its characteristics (intensity, frequency etc) as well as we would like to see.

As the first study makes clear, future changes in extreme precipitation are likely to be worse than the models suggest.

In an extended interview last year on the subject, Trenberth explained:

“I find it systematically tends to get underplayed and it often gets underplayed by my fellow scientists. Because one of the opening statements, which I’m sure you’ve probably heard is “Well you can’t attribute a single event to climate change.” But there is a systematic influence on all of these weather events now-a-days because of the fact that there is this extra water vapor lurking around in the atmosphere than there used to be say 30 years ago. It’s about a 4% extra amount, it invigorates the storms, it provides plenty of moisture for these storms and it’s unfortunate that the public is not associating these with the fact that this is one manifestation of climate change. And the prospects are that these kinds of things will only get bigger and worse in the future.”

Let’s hope these new studies helped put an end to the underplaying of the link between human caused emissions and the extreme weather events we are experiencing now.

The Washington Post has a good piece on the two studies, “Greenhouse gases led to increase in deluges, researchers say,” with more quotes:

“Human influence on the climate system has the effect of intensifying precipitation extremes,” said Francis Zwiers, a climate researcher at Environment Canada in Toronto and lead researcher on the first study.

Zwiers and his team gathered 50 years of rainfall statistics, and compared those observations to predictions made by computer simulations of the 20th century climate.

Those simulations included the warming impact of the billions of tons of carbon dioxide human society has pumped into the atmosphere.

The study found that observed increase in deluges “cannot be explained by natural internal fluctuations of the climate system alone,” said Zwiers. In other words, only the addition of greenhouse gases to the atmosphere explains why the United States and Canada have experienced a dramatic increase in heavy downpours.

“Large [rainfall] events are becoming larger,” Zwiers said. His work found that from 1951 to 1999, the probability of heavy downpours becoming even more extreme grew by about 7 percent, a figure he characterized as “really substantial.”

Richard Allan, a climate scientist at the University of Reading in England who was not part of the study, called the method employed by Zwiers “very rigorous.”

He added, “There’s already been quite a bit of evidence showing that there has been an intensification of rainfall” events across the globe.

But until now “there had not been a study that formally identified this human effect on precipitation extremes,” Zwiers said. “This paper provides specific scientific evidence that this is indeed the case.”

Note that these studies do not extend beyond the year 2000, so they miss the hottest decade on record and the wettest year on record.

You can see some of the amazing photos from the 2000 UK floods here.

Floods 2000: Flooding from River Trent

Here’s some more quotes from leading scientists via Seth Borenstein’s AP story:

Both studies should weaken the argument that climate change is a “victimless crime,” said Myles Allen of the University of Oxford. He co-authored the second study, which connected flooding and climate change in the United Kingdom. “Extreme weather is what actually hurts people.”

Jonathan Overpeck, a University of Arizona climate scientist, who didn’t take part in either study, praised them as sensible and “particularly relevant given the array of extreme weather that we’ve seen this winter and stretching back over the last few years.”

… “Put the two papers together and we start to see an emerging pattern,” said Andrew Weaver of the University of Victoria, who wasn’t part of either study. “We should continue to expect increased flooding associated with increased extreme precipitation because of increasing atmospheric greenhouse gas. And we have no one to blame but ourselves.”

Let’s run through some of the other recent studies that support the conclusion that human-caused global warming is making weather more extreme:

Study: Global warming is driving increased frequency of extreme wet or dry summer weather in southeast, so droughts and deluges are likely to get worse

A new study by a Duke University-led team of climate scientists suggests that global warming is the main cause of a significant intensification in the North Atlantic Subtropical High (NASH) that in recent decades has more than doubled the frequency of abnormally wet or dry summer weather in the southeastern United States….

The models – known as  Coupled Model Intercomparison Project Phase 3 (CMIP3) models – predict the NASH will continue to intensify and expand as concentrations of carbon dioxide and other greenhouse gases increase in Earth’s atmosphere in coming decades.”This intensification will further increase the likelihood of extreme summer precipitation variability – periods of drought or deluge – in southeastern states in coming decades,” Li says.

And one of my commenters posted this list in response to the nonsensical quote by Pielke in the Wall Street Journal, “There’s no data-driven answer yet to the question of how human activity has affected extreme weather”¦.”  The first three may be the most relevant.

Some observational, modelling and observational and modelling studies concerning the trends in temperature extremes and precipitation intensity. I have limited myself to material that has been released since 2007 (when the last IPCC report was released); this is by no means a complete list. Not all of them directly challenge the claim about human activities affecting extreme weather, but I included them because they point to a coherent picture.

Zhang et al. (2007): Detection of human influence on twentieth-century precipitation trends. (Nature)
We show that anthropogenic forcing has had a detectable influence on observed changes in average precipitation within latitudinal bands, and that these changes cannot be explained by internal climate variability or natural forcing. We estimate that anthropogenic forcing contributed significantly to observed increases in precipitation in the Northern Hemisphere mid-latitudes, drying in the Northern Hemisphere subtropics and tropics, and moistening in the Southern Hemisphere subtropics and deep tropics. The observed changes, which are larger than estimated from model simulations, may have already had significant effects on ecosystems, agriculture and human health in regions that are sensitive to changes in precipitation, such as the Sahel.”

Christidis et al. (2011): The role of human activity in the recent warming of extremely warm daytime temperatures. (J. Climate).
“Our analysis is the first that attempts to partition the observed change in warm daytime extremes between its anthropogenic and natural components and hence attribute part of the change to possible causes. Changes in the extreme temperatures are represented by the temporal changes in a parameter of an extreme value distribution. Regional distributions of the trend in the parameter are computed with and without human influence using constraints from the global optimal fingerprinting analysis. Anthropogenic forcings alter the regional distributions, indicating that extremely warm days have become hotter.”

Zwiers et al. (2010): Anthropogenic Influence on Long Return Period Daily Temperature Extremes at Regional Scales. (J. Climate).
We therefore conclude that the influence of anthropogenic forcing has had a detectable influence on extreme temperatures that have impacts on human society and natural systems at global and regional scales. External influence is estimated to have resulted in large changes in the likelihood of extreme annual maximum and minimum daily temperatures. Globally, waiting times for extreme annual minimum daily minimum and daily maximum temperatures events that were expected to recur once every 20 years in the 1960s are now estimated to exceed 35 and 30 years respectively. . In contrast, waiting times for circa 1960s 20-year extremes of annual maximum daily minimum and daily maximum temperatures are estimated to have decreased to less than 10 and 15 years respectively.”

Krishnamurthy et al. (2009): Changing Frequency and Intensity of Rainfall Extremes over India from 1951 to 2003. (J. Climate).
“Statistically significant increasing trends in extremes of rainfall are identified over many parts of India, consistent with the indications from climate change models and the hypothesis that the hydrological cycle will intensify as the planet warms. Specifically, for the exceedance of the 99th percentile of daily rainfall, all locations where a significant increasing trend in frequency of exceedance is identified also exhibit a significant trend in rainfall intensity.”

Teixeira and Satyamurty (2011): Trends in the Frequency of Intense Precipitation Events in Southern and Southeastern Brazil during 1960-2004. (J. Climate).
“In both regions, annual heavy and extreme rainfall event frequencies present increasing trends in the 45-year period. However, only in Southern Brazil is the trend statistically significant. Although longer time series are necessary to ensure the existence of long term trends, the positive trends are somewhat alarming since they indicate that climate changes, in terms of rainfall regimes, are possibly under way in Brazil.”

Ding et al. (2009): Changes in hot days and heat waves in China during 1961-2007. (Int. J. Clim.)
“Over most of China except northwestern China, the frequency of HDs was high during the 1960s-1970s, low in the 1980s, and high afterwards, with strong interannual variations. A remarkable increasing trend of HDs occurred after the 1990s in all regions. ”

Rodda et al.(2009): A comparative study of the magnitude, frequency and distribution of intense rainfall in the United Kingdom. (Int. J. Clim).
“Most noticeably, increases up to 20% have occurred in the north-west of the country and in parts of East Anglia. There have also been changes in other areas, including decreases of the same magnitude over central England. The implications of these changes are considered.”

Kysel½ (2009): Recent severe heat waves in central Europe: how to view them in a long-term prospect? (Int. J. Clim).
“Owing to an increase in mean summer temperatures, probabilities of very long heat waves have already risen by an order of magnitude over the recent 25 years, and are likely to increase by another order of magnitude by around 2040 under the summer warming rate assumed by the mid-scenario. Even the lower bound scenario yields a considerable decline of return periods associated with intense heat waves. Nevertheless, the most severe recent heat waves appear to be typical rather of a late 21st century than a mid-21st century climate. ”

Gallant and Karoly (2010): A Combined Climate Extremes Index for the Australian Region (J. Climate)
“Over the whole country, the results show an increase in the extent of hot and wet extremes and a decrease in the extent of cold and dry extremes annually and during all seasons from 1911 to 2008 at a rate of between 1% and 2% decade21. These trends mostly stem from changes in tropical regions during summer and spring. There are relationships between the extent of extreme maximum temperatures, precipitation, and soil moisture on interannual and decadal time scales that are similar to the relationships exhibited by variations of the means. However, the trends from 1911 to 2008 and from 1957 to 2008 are not consistent with these relationships, providing evidence that the processes causing the interannual variations and those causing the longer-term trends are different.”

Romps (2011): Response of Tropical Precipitation to Global Warming. (J. Atmos. Sci.)
“There are many properties of convection that can change as the atmosphere warms, each of which could produce deviations from CC scaling. These properties include the effective water-vapor gradient, cloud pressure depth, and cloud velocity. A simple theory is developed that predicts the changes in these properties consistent with CC scaling. Convection in the cloud-resolving simulations is found to change as predicted by this theory, leading to an ~20% increase in local precipitation fluxes when the CO2 concentration is doubled. Overall, an increase in CO2 leads to more vigorous convection, composed of clouds that are wider, taller, and faster.”

Wentz et al. (2007): How Much More Rain Will Global Warming Bring? (Science).
“Climate models and satellite observations both indicate that the total amount of water in the atmosphere will increase at a rate of 7% per kelvin of surface warming. However, the climate models predict that global precipitation will increase at a much slower rate of 1 to 3% per kelvin. A recent analysis of satellite observations does not support this prediction of a muted response of precipitation to global warming. Rather, the observations suggest that precipitation and total atmospheric water have increased at about the same rate over the past two decades.”

Allan et al. (2010): Current changes in tropical precipitation. (Environmental research letters).
“Analysing changes in extreme precipitation using daily data within the wet regions, an increase in the frequency of the heaviest 6% of events with warming for the SSM/I observations and model ensemble mean is identified. The SSM/I data indicate an increased frequency of the heaviest events with warming, several times larger than the expected Clausius-Clapeyron scaling and at the upper limit of the substantial range in responses in the model simulations.”

Allan and sodden (2008): Atmospheric Warming and the Amplification of Precipitation Extremes. (Science).
“We used satellite observations and model simulations to examine the response of tropical precipitation events to naturally driven changes in surface temperature and atmospheric moisture content. These observations reveal a distinct link between rainfall extremes and temperature, with heavy rain events increasing during warm periods and decreasing during cold periods. Furthermore, the observed amplification of rainfall extremes is found to be larger than that predicted by models, implying that projections of future changes in rainfall extremes in response to anthropogenic global warming may be underestimated.”

Lenderink and Meijgaard (2008) Increase in hourly precipitation extremes beyond expectations from temperature changes. (Nature).
“Indeed, changes in daily precipitation extremes in global climate models seem to be consistent with the 7% increase per degree of warming given by the Clausius-Clapeyron relation3, 4, but it is uncertain how general this scaling behaviour is across timescales. Here, we analyse a 99-year record of hourly precipitation observations from De Bilt, the Netherlands, and find that one-hour precipitation extremes increase twice as fast with rising temperatures as expected from the Clausius-Clapeyron relation when daily mean temperatures exceed 12″‰°C. In addition, simulations with a high-resolution regional climate model show that one-hour precipitation extremes increase at a rate close to 14% per degree of warming in large parts of Europe. Our results demonstrate that changes in short-duration precipitation extremes may well exceed expectations from the Clausius-Clapeyron relation. “

Of course, don’t miss Table 3.8 in the IPCC’s Fourth Assessment, Working Group I: The Physical Science Basis.

Finally, we have one of my favorites, Record high temperatures far outpace record lows across U.S.:

temps

Spurred by a warming climate, daily record high temperatures occurred twice as often as record lows over the last decade across the continental United States, new research shows. The ratio of record highs to lows is likely to increase dramatically in coming decades if emissions of greenhouse gases continue to climb.

So yes, key weather events are becoming more extreme — especially deluges, heat waves, and droughts — as climate scientists have long predicted they would if atmospheric concentrations of greenhouse gases kept rising.  And now we have solid attribution of that increase in extreme weather to human emissions in multiple independent studies.

So let’s move on from that “debate” and focus on how we best minimize the damage from future warming — aggressive greenhouse gas mitigation plus adaptation.

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50 Responses to Two seminal Nature papers join growing body of evidence that human emissions fuel extreme weather, flooding that harm humans and the environment

  1. Prokaryotes says:

    The next time someone wants to debunk climate science show him above list about uptake of weather extremes.

  2. Wit's End says:

    The UK Guardian has posted a photo gallery of the flood of 2000:

    http://www.guardian.co.uk/environment/gallery/2011/feb/16/floods-2000-climate-change-pictures#/?picture=371763962&index=0

    Pretty amazing, shots, especially the grocery store.

  3. Prokaryotes says:

    Mentions briefly floods & fires, compares 2008 food crisis.

    Video, World Bank: Chronic hunger to affect 1 billion http://edition.cnn.com/2011/BUSINESS/02/15/world.bank.hunger.prices.ft/index.html?hpt=T2

  4. Prokaryotes says:

    Renewable energy could revive council coffers

    Councils facing budget cuts could make savings and create jobs by using green energy incentives, says Simon Parker
    http://www.guardian.co.uk/society/joepublic/2011/feb/16/renewable-energy-ease-council-cuts

  5. Michael T. says:

    Another study on rising sea level:

    Rising seas threaten 180 U.S. cities by 2100: study

    WASHINGTON (Reuters) – Rising seas spurred by climate change could threaten 180 U.S. coastal cities by 2100, a new study says, with Miami, New Orleans and Virginia Beach among those most severely affected.

    Previous studies have looked at where rising waters might go by the end of this century, assuming various levels of sea level rise, but this latest research focused on municipalities in the contiguous 48 states with population of 50,000 or more.

    Cities along the southern Atlantic coast and the Gulf of Mexico will likely be hardest hit if global sea levels rise, as projected, by about 3 feet (1 meter) by 2100, researchers reported in the journal Climate Change Letters.

    http://news.yahoo.com/s/nm/20110216/ts_nm/us_climate_usa_cities_1

  6. sasha says:

    Thanks for the reads :)

  7. Prokaryotes says:

    Extreme Storms and Floods Concretely Linked to Climate Change?

    Growing Odds of Rising Floodwaters

    In separate research, Pardeep Pall and colleagues studied the historic and extremely destructive floods that inundated England and Wales in the autumn of 2000, the wettest autumn in a record dating back to 1766. Their goal was determining how greenhouse gas-driven warming might have changed the odds of this specific type of damaging weather event.

    Pall, of the Institute for Atmospheric and Climate Science in Zurich, Switzerland, tied human-influenced warming patterns to elevated odds of floods caused by a specific displacement of the North Atlantic jet stream—the same type of event that caused the fall 2000 floods.

    His team created and ran thousands of computer climate simulations models—even tapping a large network of off-hours home computers volunteered by weather enthusiasts through the distributed computing project climateprediction.net. http://news.nationalgeographic.com/news/2011/01/110116-climate-change-greenhouse-gas-floods-storms-water/

  8. Prokaryotes says:

    Floods linked to manmade climate change: studies

    Man-made greenhouse gas emissions are linked to more frequent heavy rainfall, two studies published found on Wednesday, portraying a clearer human fingerprint after a spate of floods around the world.

    Scientists agree that greenhouse gas emissions are warming the world and expect that in turn would lead in the future to more evaporation of water, more moist air and heavier rainfall.

    But the two new papers were the first to pin an increase in heavy rainfall in the second half of the last century directly on climate change, as well as one particular extreme flood in Britain.

    “The two studies demonstrate that a human impact upon the intensification of rainfall and associated flooding is already detectable,” said Richard Allan at the department of meteorology, University of Reading, in Britain.

    http://www.reuters.com/article/2011/02/16/us-climate-rainfall-idUSTRE71F6BG20110216

  9. Bill Waterhouse says:

    Here in Southern California we’re having above-average rains and about to get hit by an atmospheric river storm all during La Niña conditions when we’re supposed to be dry. Anyone seen a scientific paper trying to explain this?

  10. sidd says:

    I would probably be amused at the inevitable Pielke rejoinder, if I were to read it, but I shan’t so I won’t.

  11. MapleLeaf says:

    Thanks for featuring those papers Joe. I just don’t know how much more evidence people want. Seriously do Obama’s science advisors not read the scientific literature?

    People should also read this post at Bart Verheggen’s site concerning sea-level rise:

    http://ourchangingclimate.wordpress.com/2011/01/19/sea-level-versus-temperature/

  12. Scrooge says:

    When I read this it makes me think the NCAR drought index models may be to conservative on the timing.

  13. Prokaryotes says:

    Nature podcast for the story

    Here comes the flood
    Anthropogenic greenhouse gases increase the risk of heavy rainfall and flooding http://www.nature.com/nature/podcast/index-2011-02-17.html

  14. Colorado Bob says:

    Storms have hit again near Melbourne and Adelaide, from the ones near Adelaide –

    BAROSSA Valley residents will continue their clean-up today in the wake of a two-hour deluge that caused the area’s second flash flood this summer.

    http://www.adelaidenow.com.au/ipad/roads-turn-to-rivers-and-still-more-rain-to-come/story-fn6bqphm-1226007221593

    Grape grower Harry Schultz, of Kalimna Vineyard, 2km north of Nuriootpa, said his rain gauge had been inundated.

    “I got the surprise of my life. I’ve never seen it this full in 15 years of checking,” he said.

    Mr Schultz’ rain gauge only reads up to 120mm. He hoped more rain stayed away so his crop could recover.

  15. Colorado Bob says:

    Insurers face consequences of global warming
    Some companies are refusing to write new policies on waterfront properties because they say it’s too risky

    Meteorological forecasts showed a 40 percent greater chance of a strong hurricane making landfall on the Eastern Seaboard this year than in previous seasons. A spate of catastrophic storms that have hit the Gulf Coast in recent years also led home insurers to reassess their risk levels.

    ‘‘Two years ago, three years ago, we never would have thought our exposure would be as great as it is,” said Jeff Williams, Allstate’s regional counsel. Now, he said, the hurricane risk is ‘‘virtually uninsurable.”

    http://www.gazette.net/stories/021607/polinew204537_32320.shtml

  16. Sou says:

    Sometimes even seminal works only confirm what those in regions of increased deluges, floods, snowstorms and record temperatures already know. Perhaps a person has to be older to appreciate these changes. For younger people it’s becoming the new normal.

    Although I know that memory plays tricks, rain gauges and flood markers and thermometers rarely lie consistently. And when you have to install bigger guttering and dig trenches to keep the intense storm rain out, and keep a stock of sandbags in the garage for those extra heavy deluges, or install an air conditioner to be comfortable, and summer bushfires are annual instead of one in 30 year events, it should be quite plain that something unusual is happening to the weather.

  17. Almost did not cover this because I’ve done a lot extreme event stories. However worked in another study:

    “Fortunately, another new report shows the world can end its addiction to climate-wrecking fossil-fuel energy by 2050″.

    http://ipsnews.net/news.asp?idnews=54505

  18. Aaron Lewis says:

    How come when guys predict neutrinos, a few data points confirm the theory, but when we predict global warming, floods of data do not count?

  19. cr says:

    BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF MONTANA:

    NEW SECTION. Section 1. Public policy concerning global warming. (1) The legislature finds that to ensure economic development in Montana and the appropriate management of Montana’s natural resources it is necessary to adopt a public policy regarding global warming.

    (2) The legislature finds:

    (a) global warming is beneficial to the welfare and business climate of Montana;

    (b) reasonable amounts of carbon dioxide released into the atmosphere have no verifiable impacts on the environment; and…

    http://scienceblogs.com/tfk/2011/02/montana_legislature_thinks_glo.php

  20. Bob Lang says:

    Stephen Leahy #17

    Fortunately, another new report shows you can

    “Cure Cancer with Magnets”

    http://www.stopcancer.com/magnetswollenrpt.htm

  21. Matt says:

    Missing “not” from the statement immediately following the Washington Post quote.

    Note that these studies do extend beyond the year 2000, so they miss the hottest decade on record and the wettest year on record.

    [JR: TY]

  22. Mike says:

    Another shocker:

    http://nsidc.org/news/press/20110216_permafrost.html
    16 February 2011
    Thawing permafrost will accelerate global warming in decades to come, says new study

    One- to two-thirds of Earth’s permafrost will disappear by 2200, unleashing vast quantities of carbon into the atmosphere, says a study by researchers at the Cooperative Institute for Research in Environmental Sciences (CIRES) National Snow and Ice Data Center (NSIDC).

    “The amount of carbon released is equivalent to half the amount of carbon that has been released into the atmosphere since the dawn of the industrial age,” said NSIDC scientist Kevin Schaefer. “That is a lot of carbon.”

    The carbon from permanently frozen ground—known as permafrost —will make its impact, not only on the climate, but also on international strategies to reduce climate change Schaefer said. “If we want to hit a target carbon concentration, then we have to reduce fossil fuel emissions that much lower than previously calculated to account for this additional carbon from the permafrost,” Schaefer said. “Otherwise we will end up with a warmer Earth than we want.”

  23. Dr.A.Jagadeesh says:

    Excellent article.

    Yes. Human emissions fuel extreme weather, flooding that harm humans and the environment

    Human societies over the ages have depleted natural resources and degraded their local environments. Populations have also modified their local climates by cutting down trees or building cities. It is now apparent that human activities are perturbing the climate system at the global scale. Climate change is likely to have wide-ranging and potentially serious health consequences. Some health impacts will result from direct-acting effects (e.g., heat wave-related deaths, weather disasters); others will result from disturbances to complex ecological processes (e.g., changes in patterns of infectious disease, in freshwater supplies, and in food production).

    Natural Disasters. Climate change will increase the risk of both floods and droughts. Ninety percent of disaster victims worldwide live in developing countries, where poverty and population pressures force growing numbers of people to live in harm’s way—on flood plains and on unstable hillsides. Unsafe buildings compound the risks. The vulnerability of those living in risk-prone areas is perhaps the single most important cause of disaster casualties and damage.

    Dr.A.Jagadeesh Nellore(AP),India

  24. Villabolo says:

    @9 Bill Waterhouse:

    Bill, the situation is more complex. La Niña conditions are being interfered with by other weather events. The link below should be of help.

    http://www.sierraphotography.com/wxnotes/default,month,2011-01.aspx

  25. MapleLeaf says:

    Joe,

    “Note that these studies do not extend beyond the year 2000, so they miss the hottest decade on record and the wettest year on record.”

    Excellent point, and yet they still found a significant signal…..

  26. Mulga Mumblebrain says:

    Can anyone say by how much the added water vapour exacerbates the warming trend, because this looks like a positive feedback already at work, and one that I assume will be hard to reverse. In the last couple of days parts of Darwin have received 600-700 mm of rain from a near-miss by a Category One cyclone. There’s a hell of a lot of water falling from the sky already. Oh, and by how much will the added water vapour make electric storms more intense, as I assume that it will.

  27. Sime says:

    “Let’s hope these new studies helped put an end to the underplaying of the link between human caused emissions and the extreme weather events we are experiencing now.”

    Well they did for one former Skeptic, Weather Channel’s Ostro who reviews this Wild Winter and changes his stance to convinced…

    http://www.youtube.com/watch?feature=player_embedded&v=gwMrpRdHjkQ

  28. Sime says:

    This is a really cool way of circumventing the denier BS, by simply pressing the human greed button and ignoring the BS regardless of whether you believe climate science or not!

    As the guy in the trailer below says…

    “…So if you don’t give a dam about the environment, do it because you are a greedy bastard and you just want cheap power!”

    And as an extra bonus it gives you the ability to give the big fat middle finger to oil companies and the likes of the Koch clan and some very ignorant politicians… yum… sweet!

    http://www.youtube.com/watch?v=US7WoExxxPQ&feature=related

    Take your friends to the movie when it is released.

  29. James says:

    The 2000 British floods were extreme but were certainly not a lone event. In 2007 large parts of the country were again hit by floods. It was the wettest May/June since records began and there was many extreme downpours like those mentioned in this article (e.g. 1 months rainfall in 24 hours)

    My own region of Gloucestershire was particularly badly affected as floodwater contaminated the drinking water supply. Being unable to get water from taps for a fortnight was a horrible experience. It also showed me how limited cost-benefit analysis of climate change are; what price clean water? (Bjorn Lomborg and your ilk, I’m talking to you!)

  30. Peter M says:

    I have seen what extreme weather can do- here in CT- the blizzards and ice caused water to enter my home- the structures here where not designed for this kind of weather event.

    Roof cave ins (many) to homes, schools and businesses. Nary a word from the local meteorologists that something ‘might be wrong’. Never in state history have winter storms caused so much chaos. What could be on the horizon for summer- I care not venture there.

    Water soaked by carpets upstairs- into the pad. Releasing a toxin and mold that has made my very ill. I had to tear up the padding that was exposed to the water. Still there is a faint smell- I have to sleep in the other bedroom- and transferred the computer there as well.

    Went to the ER Tuesday morning- I was so ill. Insurance adjuster called yesterday- said with all these claims premiums will rise- sure they many do not go belly up.

    Welcome to the New Age of Climate Disruptions- its sure to get worse- and soon. Sick, and fed up in Connecticut.

  31. Larry Gilman says:

    Maybe too quick to praise the Times? As of right now, 8:46 AM EST, the headline at the article you linked to says merely “Heavy Rains LInked to Humans.” Ditto for the Global Edition front-age headline at http://global.nytimes.com/.

    What happened to “snow”? Did the editors not understand that “precipitation” includes all water that falls from the sky? Or did they fear that reporting too much reality would damage the paper’s credibility?

    Viewed cynically, the latter, maybe. Next up from the Paper of Record: Judith Miller reveals that according to her special secret unreliable sources, climate scientists at the Climatic Research Unit are harboring weapons of mass destruction!

  32. #20 Bob, I see you have a problem with the Ecofys study. They are a very reputable energy consultancy with a 20+year track record. Can you offer some detailed critiques of their analysis? (pls contact me directly)

  33. peter whitehead says:

    UK TV (BBC,SKY,ITV) covered this flood research well. The fact that Oxford University was involved makes it difficult for the climate vampires to do their usual attacks.

  34. Bob Lang says:

    Stephen Leahy #33

    Critique their analysis???

    What analysis. There is no analysis anywhere in their “report”.

    Lots of irrelevant glitzy photos, artist’s impressions, pseudo charts with no data, no actual data anywhere in the report, etc.

    If you want to get an impression of the magnitude of the challenge we face, watch the following video of part 3 of a lecture delivered at M.I.T. last year by Obama’s chief science advisor John Holdren (not sure if his data even accounts for economic growth from 2010-50):

    http://videos.wittysparks.com/id/711964055

  35. Colorado Bob says:

    Cyclone Bingiza to Worsen Mozambique, Madagascar Floods, UN Says

    Flooding in southern Africa has affected South Africa, Mozambique, Madagascar, Zimbabwe, Namibia and Angola during the last eight weeks. Crop damage in South Africa, the continent’s largest economy, could cost the nation more than $282 million after grape farms were submerged, while OCHA estimates that almost 1 percent of Mozambique’s crops have been destroyed by rising water.

    Floods in Lesotho, a mountainous, land-locked country surrounded by South Africa, lost at least 672 homes and more than 4,700 livestock to floods that led to outbreaks of diarrhea and dysentery in both humans and animal herds, OCHA said.

    http://www.bloomberg.com/news/2011-02-17/cyclone-bingiza-may-worsen-flooding-in-mozambique-and-madagascar-un-says.html

  36. John Mason says:

    George Monbiot posted a piece in the Guardian on this, too:

    http://www.guardian.co.uk/environment/georgemonbiot/2011/feb/16/climate-change-extreme-weather

    It’s generated a bit of a trollfest unfortunately!

    Cheers – John

  37. Lou Grinzo says:

    Once again, I’m drawn back to the topic of cultural tipping points, as in “when will something happen that’s so big and so hard to deny that it will jolt Americans into acting in their own best interest?” This post and some of the comments just might hold a clue: The various financial penalties from not taking action (technically decades ago) will continue to rise and will soon reach a point where we can accurately refer it as a climate tax. The difference being that we won’t be paying, for example, a carbon tax that’s used to promote energy efficiency and renewable power, but will instead be bailing out (or moving!) coastal cities, helping parts of the US southwest deal with drought, and constantly rushing aid to various flood zones.

    I know, I know — I’m succumbing to the siren call of optimism again. If the mountain of hard data we have now won’t change anyone’s mind, why would a graph showing a hockey stick curve of rising disaster costs be any more successful?

  38. #33 Bob. Did you read the Ecofys part of the report which starts at pg 103 in the 256 page report? Its Part Two. Please contact me directly (via my website link above) w yr specific criticisms. They don’t underestimate the scale of the challenge nor do I.

    “Paramount will be major increases in energy efficiency in all sectors so that by 2050 energy use is 15 per cent less than the energy use in 2005″

    http://www.ecofys.com/com/publications/The-Energy-Report-Ecofys.htm

  39. Bob Lang says:

    Stephen #39

    Why would I give you my e-mail?

    What makes you think your non-scientific background gives you the expertise necessary to judge technical reports. Rigorous scientific methodology is required to determine the validity of “solutions”.

    This report has never been published in a peer-reviewed scientific journal.

    There are plenty of peer-reviewed studies which show that the “solutions” proposed in this report are delusional, including an online slide show by a prominent Canadian ecologist:

    http://www.slideshare.net/josswinn/bill-rees-the-vulnerability-and-resilience-of-cities

    http://journalofcosmology.com/ClimateChange108.html

  40. Steve Bloom says:

    Re #40: ‘What makes you think your non-scientific background gives you the expertise necessary to judge technical reports. Rigorous scientific methodology is required to determine the validity of “solutions”.’

    No, such reports involve a lot more than just “rigoorus scientific methodology,” (sic) e.g. policy analysis, economics and engineering.

    That basic error plus your hostile tone to a polite request for information leads me to place zero weight on your assertions.

    But speaking of scientific backgrounds, what’s yours exactly? I don’t recall seeing your name associated with any relevant publications. Even if you are some sort of scientist, it would be more than peculiar for you to decide that an experienced science journalist like Stephen isn’t worth talking to.

    Re those links, it’s a perspective that I share and I’m sure Stephen shares, but criticizing what amounts to a crash program to get off of fossil fuels on the basis that it fails to address other aspects of sustainability is off the mark. I don’t want to sell those other aspects short, but the fact is we *need* such a program on a priority basis.

  41. Steve Bloom says:

    Re #38: The future is now, Lou, noting that the Oz government wants to cut climate/energy program funding to pay for cleaning up the mess. The Green proposal that perhaps the coal industry might be asked to chunk in via a special tax was roundly derided. The short-term thinking is appalling.

  42. Mulga Mumblebrain says:

    Steve Bloom #42, believe me, Dunning and Kruger had Australian politicians in mind when they made their findings. Another problem is that the Howard pathocracy, the moral, intellectual and spiritual nadir (so far) of this country’s history, ruthlessly stacked the public service with hard Right ideologues. Howard itself was resolutely of the ‘all Greenies are Communists and global warming is their plot to destroy capitalism’ school, and still is, as far as I can tell. The Labour regimes since 2007 have done nothing to purge these ideologues, and one, the euphoniously named Godwin Grech, almost brought down Rudd with faked e-mails from his redoubt in the Treasury. Rudd was later ‘terminated with extreme prejudice’ by his own colleagues. Unfortunately the Labour Party, in its move to become ideologically acceptable to Rupert Murdoch and his ilk, the country’s real rulers, has attracted a generation of rank opportunists and intellectual nullities, and has prove amazingly incompetent, and many Ministers are plainly manipulated by their neo-liberal, Rightwing, public service controllers. Hence the unbelievably stupid and vicious imbecility of slashing green programs to meet the cost of climate disruption induced weather disasters.

  43. Bob Lang says:

    Steve #41

    Thanks for your very valid input.

    No hard feelings, I hope.

  44. David B. Benson says:

    Mulga Mumblebrain — Watrr vapor content of the atmosphere goes up ~4% per 1 K of warming.

    [JR: 7%?]

  45. John Mason says:

    ~4% per degree F; ~7% per degree C. It depends whether you like new or old money, as we say over here in the UK!

    Cheers – John

  46. Once again, the scientists were too conservative in their earlier reports (and even this modelling is seriously estimated). This will always be the case as we can all guess what is likely before we have the hard data to back it up. Scientists are only interested in what the hard data proves, not what can be infered from it.

    We don’t need papers that give the hard data we need assessments that set out the likely outcomes. And at present the outcomes are horific (and likely to get more horific as we go on).

    Its hard to keep people interested when its always disaster your spouting. These papers just make it more imperitive that we continue to shout STOP.

  47. Robert Green says:

    One can show all the evidence and papers one wants to climate deniers, they will still deny. The US budget actions towards the EPA and NOAA taken by the US House of Reps is chilling and dangerous. But they are not paying attention to the science or danger.

    So we have to shift the discussion away from “is there or is there not global warming”. We have to shift the debate to the essence of their recklessness. That is, this planet cannot afford to take the risk of inaction. We cannot afford to be wrong. It does not matter who is right, it is deadly behavior to ignore your flight instruments. And the US House is dragging us all into risk taking no reasonable person would assume.

    Start with coining a new motto: i.e. STOP PLAYING CHIKKEN WITH THE PLANET! Everybody will understand that risk.

  48. Lisa Boucher says:

    Even though it’s late, I would like to add that the nitpicking by Andrew Revkin is extremely unhelpful.  With friends like that, who needs enemies?  His remarks about the Nature papers are now being used in the cut-and-paste repertoire of deniers.

  49. Prokaryotes says:

    Revkin is exchanging emails with Monckton, what do you expect?