Sunday, September 15, 2013

Dear Bjorn: if you spend money to reduce a problem and the problem's reduced, that doesn't magically mean the problem reduced itself

One piece of Lomborg's alleged evidence that climate change hasn't produced extreme weather:  "Damage from flooding in the United States has declined from 0.2 percent of gross domestic product in 1940 to less than 0.05 percent today."

I vaguely remembered seeing this lame argument before, and after I clicked his source link I saw a familiar piece of liver. Should've guessed.

The problem with this argument is that the vast majority of money spent on flood control activities happened after 1940, and the damage-reduction effect of those flood control expenditures is incremental (flood control projects typically last 30-50 years, and rebuilding is cheaper than the original building). Extreme storm precipitation could get worse and the damage could still decrease, if you put in some effort at flood control. There's no accounting in the data set for the cost of that effort.

That's only one of many problems with Lomborg, but it's in my bailiwick so I had to call it out. And btw, the data doesn't include Sandy damages (the NOAA flood loss data set ended in September 2012), so that also might end up being a disturbance in the Force of the trend line.

33 comments:

  1. Nice "trick" Lomborg uses to normalize flood damage to GDP, which has increased from about $103 billion to $16.2 trillion from 1940 to 2012 (in 2009 dollars; source: Bureau of Economic Analysis). Lomborg's statistic was obviously contrived to hide the increased frequency of extreme weather and the cost of related damage.

    Taylor B

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  2. Using BEA's GDP values and Lomborg's statistic, one can estimate the absolute value of flood related damages (in 2009 dollars) to have increased from about $206 million in 1940 to $8.1 billion in 2012. I'd just add that while it makes sense to normalize the cost of flood damage to some measure of the increased value of infrastructure and economic activity exposed to the risk of flooding, using national GDP doesn't seems like an appropriate denominator. It's conveniently chosen by Pielke Jr. and Lomborg because it has grown much more rapidly than the value of flood-related damage. Their choice implies the assumption that the share of GDP attributed to areas exposed to flooding risk is increasing at the same rate as the share of GDP outside the at-risk areas. It's a very indirect and misleading way to measure the impacts of extreme weather. As Brian says, it assumes no changes in flood protection or building and zoning standards, as though we'd just keep building more of the same stuff in areas that have been flooded previously, and putting more stuff in harm's way (which admittedly, to some extent, the national flood insurance program has encouraged to happen). For example, much of Las Vegas lies within a flood plain. However, there's a lot of reasons to believe that GDP would be less sensitive to flood events over time, for example, changes in the structure of the economy from manufacturing and small agricultural production to financial and information services, and more robust communications, emergency response, and infrastructure. Increasing the frequency of 1,000-year and 500-year floods to 100-year floods wouldn't be reflected in Pielke/Lomborg's strategically chosen statistics.

    Taylor B

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  3. Flooding, like forest fires, indicate nothing as far as climate goes. They are both a function of human interventions, or beavers.

    Hardy Cross

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  4. Lomborg normalizing flood damages to GDP is actually the whole point of his argument.

    The Lomborg ideal is that we get richer faster than the climate gets worse.

    There's some sense in it, but if mitigation costs less than adaptation we should do it no matter how much the economy grows (just because your portfolio gains value doesn't mean you shouldn't weed out money-losing investments).

    -HAUS.MAUS

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  5. And there I was thinking that the amount of rainfall might have something to do with it. I guess the Sahara is dry because there are no beavers there then.

    Ah climate change deniers, they'd be hilarious if the issue was not so serious.

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  6. Hi Eli,

    Just posted this at Roger's in response to his latest post. I'd be curious to hear what the you and other bunnies take home message is after reading his opinion piece.

    "Hi Roger,

    I am so sorry to read of the tragic flooding in Colorado. I do hope that the missing 500 people are all OK and that the recovery efforts go well.

    Many metrics have their limitations, and that the 1 in "N" year flood has its limitations has long been known, certainly before you wrote about it in 1999. Unfortunately, just as we are stuck with the misnomer "greenhouse effect", so too we will have to live with the 1 in "N" year flood. That does not mean that we should not endeavour to develop and use better metrics.

    Fortunately, you should know that there are other metrics to consider that speak to the prodigious nature of this event. Not to mention the unusual timing when compared to previous severe flooding events. Don't make the mistake of ignoring those.

    I must admit, when you make comments like "However, being both wrong and wrongheaded does qualify the term as useful in the ongoing climate wars", you come across as belittling the current situation.

    In fact, one comes away after reading your opinion piece with the impression that you are trying to downplay the severity and (for want of a better word) uniqueness of this event. That is likely to annoy many of the people who have been less fortunate than you have been."

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  7. Brian basically nailed it. The amount of resources sunk into flood control over the years (as with hurricanes) means that standing still is losing.

    Note that Roger deals only with the extent of the flooding not with the extent of the precipitation. Flood damages are very much a function of building policy, precipitation, not so much.

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  8. Eli,

    "Flood damages are very much a function of building policy, precipitation, not so much."

    If you are referring to urban areas, then yes I agree.

    Even the rainfall amounts and precipitable water values in this case were off the charts, however.

    Roger has lost his temper with me, lumping me in with "fanatics" and "game playing ad homs" (whatever that is).

    Perhaps is because he is now being forced to experience an inkling of what the people affected by Sandy and other extreme events had to endure.

    Funny, (not) how he seemed to care not one iota of the suffering of others while he was aggressively downplaying the impact of those events.

    The timing and content of his current opinion piece is very unfortunate.

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  9. Roger has played a very tedious game for years, arguing that because you can't detect the climate signal in the noise of the data for extreme weather events, then you can't attribute any portion of extreme events to climate change. He never said it this clearly, but that's his argument.

    This backasswardness of reasoning was called out by James Annan (and by me) but Roger kept playing. Attribution is derived from theory and doesn't rely on detection in very noisy data to still be true.

    He might be getting more desperate as the signal starts overcoming the noise, making the same "overstep" he claims others do. He implies that the failure to detect a climate signal in this flooding damage means one can attribute 'no effect' of climate on flooding. He's careful enough to not say this straight out. Lomborg, less quick on the uptake, falls straight into it.

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  10. If Lomborg's slide from marginal witchhunt victim to active practitioner of the darker statistical arts continues, the grimmer Danes may revive the Scientific Dishonesty Star Chamber he escaped a decade ago.

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  11. some speculation: The difference here could be that if one is willing to pay for mitigation efforts, it doesn't count as paying. But that would ruin objectivity on financial issues of climate change. OtOH, the Wall Street hasn't been quite objective on financial issues for a long time (with their subprimes and all), so one might be deluded to think Lomborg has it correct. Taking this approach would of course 'ruin the economy' since it's not based on objective values but since there's going to be a crash one day (or so we're told) anyway, the stock market players will turn to their representatives to get some (consolation) for a crash wasn't supposed to happen since we didn't believe on it. And what does 'the man on the gas pump' say, will there be an invasion to Syria oil fields?

    well, that was a bit mangled, better formalization is clearly needed.

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  12. From the NOAA table of flood-loss data:

    "Cautions on the Accuracy of these Data

    "Flood damage estimates are reported in many different ways, and are subject to a wide variety of errors. Estimates come from federal, state, or county level government officials. If these estimations cannot be made, the reporting official from the NWS must make an approximation of the damages, a method which is prone to a high degree of subjectivity and inaccuracy. Damages are often underreported, and many times the information never makes it to the NWS Forecast Office responsible for reporting these figures. As stated above, the National Weather Service’s primary mission is providing weather information and services to save life and property, not on post-event reporting.

    "One of the most critical discrepancies of these data occurs with storm surge related flooding caused by tropical cyclones. Coastal flooding caused by storm surge is not counted in the figures presented here. The record season of 2005, with Hurricanes Katrina and Rita, were undoubtedly enormous flooding events. However, the damages and deaths associated with Hurricane Katrina were largely due to storm surge, and not fresh water flooding (associated to rainfall). Therefore, the annual figure of $43B for water year 2005, although much higher than any other year, does not account for most of the flooding produced by Katrina."


    Nor does it account for Sandy, as Brian points out, and the data which Lomborg and Pielke Jr. go so far out of their way to use as evidence of absence is no more than the absence of evidence.

    Taylor B

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  13. A couple of other things still bother me about Lomborg's and Pielke Jr.'s numbers, not that it matters much, but I don't see how they were derived.

    I can't see how they came up with losses of 0.2 percent of GDP in 1940. The single-year value in NOAA's table for 1940 is about $1.6 billion (in 2012 dollars), or 1.6 percent of GDP. Or following NOAA's example, taking the 30-year average from 1911-1940 is about 3.6 billion, or 3.7 percent of GDP. The 30-year average of flood losses in NOAA's table, therefore, slightly more than doubled between 1940 and 2012, from $3.6 to $8.2 billion, excluding damage from storm surges and without normalization to GDP.

    Taylor B

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  14. Albatross, flood damage abatement is not only effective for urban areas. Look up TVA and floods.

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  15. Taylor - there was something I didn't understand about Roger's source for GDP, I read it to say the 1940 GDP was about $96b, while another source I found said it was $1t. I just gave up on that part.

    The one concession I'd make is that if you have identical houses in 1940 and 2012 receiving identical damage in those two periods from identical floods, the economic damage will be greater in 2012 due to increased land value. The response though isn't to play games with GDP percentage, it's to compare various causes of disaster like Munich Re has done.

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  16. Hi Eli,

    We seem to be getting our wires crossed, partly because of my poorly worded response to your initial comment.

    What I was trying to say is that surface runoff in urban areas is a big issue given the preponderance of impervious surfaces and channelling by buildings etc. So rainfall amounts and intensities are a major issue there. One runs into the same problem with steep terrain too.

    Of course flood mitigation efforts (e.g., dams, floodways, dykes, diversions) can make significant differences in rural areas. As you note, the Tennessee Valley Authority (TVA) has had success in managing flood waters by building dams, for example.

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  17. Brian, I used BEA as the source for GDP, which gives 1940 GDP as about $103 billion (in 2009 dollars), while Roger's source was OMB, which says 1940 GDP was $96.8 billion (in 2005 dollars). The two sources for GDP seem to agree pretty closely. NOAA is using 2012 dollars for loss estimates. Inflation from 2005 to 2012 has been pretty low, so the different inflation adjustments shouldn't matter that much. I can't figure out how Roger gets a value of 0.2 percent of US GDP for 1940 flood losses from looking at the data he cites, though.

    Here's what IPCC's SREX summary says about adjustments to disaster losses over time. The data are a jumble, as you'd expect (emphasis is in the original):
    "Increasing exposure of people and economic assets has been the major cause of long-term increases in economic losses from weather- and climate-related disasters (high confidence). Long-term trends in economic disaster losses adjusted for wealth and population increases have not been attributed to climate change, but a role for climate change has not been excluded (high agreement, medium evidence). These conclusions are subject to a number of limitations in studies to date. Vulnerability is a key factor in disaster losses, yet it is not well accounted for. Other limitations are: (i) data availability, as most data are available for standard economic sectors in developed countries; and (ii) type of hazards studied, as most studies focus on cyclones, where confidence in observed trends and attribution of changes to human influence is low. The second conclusion is subject to additional limitations: (iii) the processes used to adjust loss data over time, and (iv) record length. [4.5.3]"

    Taylor B

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  18. Eunice would like you to remember that:

    1. Upstreamer's flood control is often downstreamer's flood cause.

    2. Floods are part of normal weather .

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  19. Nine inches of rain in a day are not part of normal weather:)

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  20. Eunice - it depends on how you do that upstream flood control. My water district has been buying streamside properties on a gradual basis for years. We rent them until we own a significant stretch, let the leases expire and then take out the buildings. That can increase upstream flood retention.

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  21. "Nine inches of rain in a day are not part of normal weather"

    Although it may be the new normal that we can look forward to. You have to wonder when the people funding climate change denial are going to start paying for the harm that they have done.

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  22. Taylor B reported that much of Las Vegas lies in a flood plane. True. The surrounding area slopes from the Northwest (12,000 foot Mount Charleston) to the SOuthEast (drains into Lake Meade).

    Around 1960, Las Vegas had a big flood, which wiped out about 300 cars in the parking lot of Caesar's Palace, located at a low spot on the Las Vegas Strip. Many of the cars were late-model luxury vehicles belonging to casino customers.

    Tourists were threatened. Profits of casinos were threatened. Needless to say, the local authorities launched an ambitious multi-year program, building a series of large retention basins to the NW side of the Strip, for flood control. If you ever visit Las Vegas, take a break and drive out to see the retention basins. They're quite impressive.

    Even with all that construction, it still floods on the ground floor of the parking lot of the Imperial Palace (across the Strip from Caesar's Palace).

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  23. Here's a link to flooding in the Las Vegas greater metropolitan area in Sept. 2013 (THIS MONTH). While it got the attention of local LV media, the story has been totally swamped by the news from Colorado.

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  24. Re Eunice being as clueless as ever, it's good to know that some things never change.

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  25. "Nine inches of rain in a day are not part of normal weather"

    Unless they're compared to eleven inches in a Colorado day that happened in 1965 or numerous other floods that are part of a normal history of weather in the US and the world.

    Those who don't recall history are destined to feelings of hysteria.

    Eunice.

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  26. What month of the year was that Eunice darling?

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  27. Eunice claims 11 inches, somewhere sometime. What a feeble attempt. I find for Boulder: "In Boulder, 7.21 inches of rain fell in just more than 15 hours, from 6 p.m. Wednesday to 9:15 a.m. Thursday, the National Weather Service said. That was 50% more than the previous record set in 1919 - 4.8 inches within 24 hours."

    "Colorado's monsoon rain season almost always ends by August."

    Rib Smokin' Bunny

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  28. Maybe it's just bad luck to name your town Las Vegas?

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  29. Although I was a wee thing, I remember when the Franklin Dam on the Merrimack was becoming filled (pre-war-2 for the US). There was a simple warning sign not to use the old road, but no real barricade. My father was curious so continued down the old road.

    My grandmother and aunt were in the car. From the back seat they kvetched that the road was closed. Bad idea.

    My father claimed that it was still passable. When we came to the water, the squawks began. My father remarked that the water wasn't all that deep. Shrieks began, full horror, telling him the road was flooded. Impervious to their back-seat driving, my father continued until the water came up to the hubcaps.

    Then he backed up. My mother said later she knew better than to say anything. Maybe he married her because she was not the shrieky type.

    -- Snow Bunny

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  30. Snow Bunny, more seriously:
    The Merrimack River's most serious flood since 1938 (ginormous hurricane) occurred in 2006 flooding some of the old mill buildings. This flood was attributed to a stalled low pressure system and more moisture content in the air and was nothing like a hurricane.

    Gee whiz, don't the climate scientists say slower jet stream motion and more rain in the air is due to global warming?

    http://en.wikipedia.org/wiki/New_England_Flood_of_May_2006

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  31. Upstreamer's flood control is often downstreamer's flood cause.

    John McPhee wrote a great book that talks about that (The Control of Nature)

    The Army Corps of Engineers features prominently (though the State of California also makes an appearance for "mud control")

    The Corps were famously responsible for the levees that "protected" New Orleans during Katrina.

    They were also even more famously responsible for drying out the Everglades (damned swamps)

    Hubris has no bounds.

    We humans screw around with extremely complex systems (like the climate and river drainages) that we have absolutely no clue about.

    And then we are surprised when they turn around and bite us in the ass.

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  32. Rib Smoker,

    Many heavy rain events don't have the courtesy to fall over a recording station,
    but those that have remind us to worry about 'normal' climate because normal includes disasters:

    http://www.wrcc.dri.edu/htmlfiles/co/co.ppt.ext.html

    Eunice

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  33. Ah, Eunice, so if the rain gauge is not hit you can't tell it rained a good old flood? Climate thing (wet part of year and dry, warm vs cold) got you puzzled, too. Life must be full of surprises for you.

    Rib Smokin' Bunny

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