Record Highs Outpace Record Lows

[n2doc]

By LiveScience Staff
posted: 15 November 2009 10:12 am ET

Daily record high temperatures occurred twice as often as record lows over the last decade across the continental United States, new research shows.

"Climate change is making itself felt in terms of day-to-day weather in the United States," said the study's lead author, Gerald Meehl of the National Center for Atmospheric Research. "The ways these records are being broken show how our climate is already shifting."

If temperatures were not warming, the number of record daily highs and lows being set each year would be approximately even, the researchers explained in a statement.

Instead, for the period from Jan. 1, 2000, to Sept. 30, 2009, the continental United States set 291,237 record highs and 142,420 record lows, as the country experienced unusually mild winter weather and intense summer heat waves.

more:

http://www.livescience.com/environment/091115-record-high-temperatures.html

[GliderGuider]

1. The graph drives the point home.

[Nederland]

2. I hate this

If temperatures were not warming, the number of record daily highs and lows being set each year would be approximately even

The problem with this statement is that it is mathematically inaccurate. It is perfectly possible for the number of daily highs to occur twice as often as daily lows and have no trend whatsoever. The key is to communicate the magnitude of the highs and lows, which the article does not do. I understand what this person was trying to say, and perhaps they got quoted wrong, but it just bugs me when statements like this get put into print because they are such easy targets for deniers.

[Viking12]

8. I'm not sure I understand your objection.

It is perfectly possible for the number of daily highs to occur twice as often as daily lows and have no trend whatsoever.

That statement is nonsense. If natural variation creates an equal distribution of chances yet we have record daily highs occurring at twice the frequency of record daily lows, we certainly do have a trend. Maybe I misunderstand your point and you could explain more clearly?

[Nederland]

9. Sorry, I'll be more clear

From a purely mathematical standpoint, it is possible to have the number of daily highs to occur twice as often as daily lows and have no trend whatsoever. The reason this is true is because I haven't said anything about the magnitude of those highs and lows. For example, if I get ten new record lows that each beat the previous record low by 4 degrees, and get twenty new record highs that each beat the previous record high by 2 degrees, the highs and lows will cancel each other out when you calculate the average temperature. I know that probably isn't what happened, but I was just frustrated at how the article simplified the concept to the point where it was no longer accurate.

[Viking12]

10. OK, now I get where you're going.

Although the scenario you use would negate any trend in the avg temp, the frequency of extremes is significant in and of itself independent of the avg temp trend. High temp records, especially in summer, are often associated with more immediate and acute consequences than the chronic problems associated with avg temp trends.

[Warpy]

3. Climate is changing

and whether its our fault or Mother Earth is just putting her own brakes on overpopulation is anyone's guess.

It seems likely food will become very scarce for a lot of people on this planet over the next couple of centuries as arable land area decreases all over the globe. The oceans are fished out and the more efficient land animals have been hunted near extinction. Hunger will drive us to finish the job.

Hunger is horrible and it hurts more than you can imagine. People are not going to die quietly. However, many of us are likely to die as climate shifts.

[Nederland]

4. I don't think hunger will be our biggest problem

Yes, as temperatures rise existing crop lands will see decreased crop production. At the same time however, vast areas of land in Canada and Russia will experience longer growing seasons resulting in increased crop production. The shift away from land near the equator that is already depleted from centuries of cultivation toward land closer to the poles that has largely never been cultivated may actually result in an increase in total global yields.

[Warpy]

5. That's not going to do any good

for people in equatorial countries and lower lattitudes in the northern hemisphere. That's where most of us live and that's where most of us will die.

[Nederland]

6. Not sure I agree

Most people already eat food that is transported to them, in many cases over long distances. Population centers do not tend to be located near food sources anymore. If they were, the largest cities in the US would be located in the mid-west.

[Warpy]

7. You might do that in the first world

but no one in the third world can afford to and I sincerely doubt many people in the first world will choose to forgo meat in order to ship things like flint corn and soybeans to the starving in Africa and India.

It's just not the way the world works.

[bhikkhu]

11. You might read up on the energy situation before relaxing much

The other major problem for the species besides climate change is the advent of peak oil. As far as agriculture and hunger and so forth, it means that the major energy input into agriculture (in fact, the centerpiece of the "Green Revolution") is becoming more expensive, harder to find, costlier to extract, and generally less suitable as an abundant energy source for fueling growth and building infrastructure.

[NickB79]

12. This is complete and utter bull

"At the same time however, vast areas of land in Canada and Russia will experience longer growing seasons resulting in increased crop production."

The fact that the growing season will be longer does not arable land make. Existing farmland will put out more yields, but to compensate for loss of farmland in southern latitudes AND a growing population, you need to add new farmland as well. No matter how nice the climate might be, you're gonna have some difficulty growing crops on the Canadian Shield. Unless you know of a genetically engineered corn that can penetrate granite, no significant farming will be done in large areas of Canada due to thin soil and hard bedrock.

"The shift away from land near the equator that is already depleted from centuries of cultivation toward land closer to the poles that has largely never been cultivated may actually result in an increase in total global yields."

Are you familiar with soil fertility in many northern regions? Have you ever read about what kinds of soils comprise much of Canada's landmass, or that of Siberian Russia? For one, their boreal forests (one of the potential new sources of farmland) grow on acidic, nutrient-poor and boggy soil, something that a longer growing season will not change.