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Coldest summer in 20 years or so

I've noticed that many Americans - members of the nation that dominates TRF visits - tend to extrapolate the events in the U.S. to the whole globe. And because the U.S. has seen a pretty warm weather, many people think that the Northern Hemisphere has experienced a warm summer.

Well, it's not the case.

In the U.K., they have seen the coldest, cloudiest, and wettest summer holidays since 1993. The London Met nostalgically remembers the heat waves in 2006 that were followed by lousy summer seasons; Summer 2011 was arguably the worst one of them, they say. If the correlation with the weather in the winter will continue, Britain will see a cold winter, too.

What about the adjacent island, McIreland? Well, Ireland has gone through the coldest June in 40 years, coldest July in 50 years, and coldest August in 25 years. It's plausible that the average of these three months were the lowest period since the records began in 1851. However, the Irish summer wasn't wet.

Somewhat less extremely, Czechia witnessed the coldest summer in 20 years, too. This can be nicely seen in the number of tropical days. Before the middle of August, the average weather station only saw 1 tropical day. The previous 7 days were warm and about 5 more tropical days were added but it's cold again so we surely can't catch up with 12 tropical days in 2010. The last 10 days of July were 3 °C below the normal. The precipitation in July was 1.6 times higher than the normal.

To be sure, not all states in America have been as hot as Texas. Oregon recorded the second coldest summer weather since the measurements began in 1891 - the coldest one was in 1916.

Some people say that those things don't matter but they do. It's the actual weather that actually matters at every moment - not some arbitrarily constructed, contrived averages. Because we keep on experiencing the same range and distribution of temperatures and other quantities as we used to decades ago, some shifts of some averages - even if they existed - can't possibly be relevant for anything we care about.

The weather is more important than the climate. The climate focuses on averages etc. but as long as the averages shift by much less than the normal natural variations of the weather, these shifts of the averages cannot be important, whatever their reason is.

Solar energy collapse

Today, another solar energy company - Solyndra - which has received half a billion dollars in subsidies from the U.S. taxpayer (yummy!) has gone bankrupt.

President Obama visits Solyndra in May 2010. He praised the company as a role model and a great green example of how the whole U.S. economy will evolve under his supervision, especially if he's allowed to be the boss of the White House for 8 years. ;-)

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reader David Evans said...

"Because we keep on experiencing the same range and distribution of temperatures and other quantities as we used to decades ago, some shifts of some averages - even if they existed - can't possibly be relevant for anything we care about."

I disagree. If the average of a distribution shifts while the variance remains the same or increases, there will necessarily be more extreme events at one end of the scale.

reader Luboš Motl said...

I agree that there will be more extremes but that doesn't contradict my statement that nothing we (you *and* me) care about is affected.

If you count the "number of extremes" defined by a particular cutoff, of course that if you shift the bell curve, the impact on this number will be substantial.

We can observe these things very easily: the number of newly set hot records is 2 times larger than the cold records in the recent decade, and so on.

But this "benchmark" is totally artificial. If you redefine the benchmark by the small shift of the temperature, the entire effect goes away. This whole effect is sensitive on very detailed definitions.

What I mean is this: imagine that the typical fluctuations for a given month are 2 degrees Celsius; that's the SD. The monthly temperatures 6 degrees above the average - assuming normal distribution for simplicity - are a 3-sigma effect which occurs each 300th month.

Obviously, you can move it to a 2.5 sigma effect if you shift the average by 1 degree - and this 2.5 sigma is surpassed each 80th month or whatever is the right number for 2.5 sigma.

However, it's still true that you may match the "extreme heat" in the previous situation with those in the new ones in such a way that the map is one-to-one and they still differ by 1 degree only which is negligible relatively to those 6 degrees of deviation that you actually care about. When it's hot, it doesn't really matter whether it's half a degree more or half a degree less - but the shift of the distribution can't do anything more than that.

So this shift won't really affect things that matter like survival rates or the average yield in agriculture etc. Try to think about these things "economically" and calculate the actual damages and you will see that this big sensitivity that you see in the Gaussian isn't there, so this "counting of the number of extremes" is just a demagogy to artificially inflate some effect that isn't important.

reader ScientistForTruth said...

Here in UK, summer has been non-existent this year. This has truly been another "year without a summer". But what did the UK MET Office predict? Well, they forecast warmer than average summers for several years and were completely wrong. They forecast warmer than average winters and were completely wrong. This year they have stopped giving seasonal forecasts to the public because they are so useless. However, before it gets taken down you can find it buried within their website so that Jo Public can't find it: the expectation for June, July and August (meteorological summer) given in May.

For London and the south east of England the results are as follows:

Probability of above average temperature >80% (two categories)
Probability of below normal temperature <20% (tercile categories)
Probability of well above normal temperatures >55% (outer quintile)
Probability of well below normal temperature approximately 5%
Probability of above normal precipitation <20% (tercile categories)

From what the MET Office themselves say, their long range climate change projections are running on the same computer with the same programme as the seasonal and daily and weekly forecasts. As year succeeds year the global warming bias that they have put into their models is making their forecasts look more and more ridiculous.

What I don't understand is why there is not more of a groundswell to say to the MET Office 'Game Over'.

reader BigLee57 said...

It is true that many here fail to realize what is occurring in America is happening globally. I think, at times, a large number of people cannot mentally fathom the actual size of the earth.

Some have attempted to attribute recent warm areas of the US to the AGW issue, CO2, etc. In reality if one pays attention to the state of the ENSO, PDO, AMO, etc then various trends in seasonal weather can be quite accurately expected. I live in the desert southwest. Last winter was mild and our summer has been moderate, our monsoon season on the dry side. All of which I anticipated.

We have had areas which were very warm this summer and ones who experienced a harsh, cold, and long winter. Both have an effect on food production which is reflected in cost and quality. But, those experiences of the seasons are not unheard of. They are very similar to what existed 50 - 60 - 70 years ago. The range of temperature in each ares consistent with times past.

So it would seem importance is on knowing what the trends in these normal shifts will be and where. With that knowledge in hand we can adjust and adapt as they occur. Such is a far better focus than worrying about a theoretical change of a few tenths degree in an arbitrary average.

I have noticed of late the duration of daylight is decreasing at rate of roughly 2 minutes per day. A fact which troubles me not. However, I have expectations of cooler temperatures in the near future. Well.... for the northern hemisphere anyway. :)

I also expect that some areas will experience 'record' cold temperatures during the coming winter and some others will experience record warm ones.