Wednesday, February 10, 2010

Global warming causes snowstorm in D.C.

At least that's what The Time Magazine and their Bryan Walsh think or at least pretend to think and tell us.

Cross-country ski used as a vehicle: that's why their ancestors were designed in the first place.

But does it? More precisely, are there any rational arguments justifying the unexpected conclusion (and preconception) of Walsh's article?

At the beginning, he tells us a lot about the conspiracies. The politicians are trying to hide the lethal threat of global warming by hiding the global warming as the cause of the snowstorm in D.C., Walsh asserts.

Walsh also says it's unlikely for top-10 storms to take place by chance in Washington D.C. as well as Philadelphia (200 km away, it's almost like light years) or even Baltimore (55 km away, that's near the Hubble scale) during the same winter. He's apparently completely unable to understand that these are just two parts of the same regional atmospheric phenomenon so their probabilities are not independent at all.

He quotes some meteorologists who claim that the snowstorm was really big - well, there exists an obvious threat in doing science in the ancient way, i.e. without numbers (with numbers replaced by emotional words). And we also hear some other old talking points: for example, the hurricanes are getting bigger, too.

But is there an argument why such a thing should be true? Well, there's no argument but there's surely something that the author considers to be an argument. In the middle of the article, we read:
That's in part because of global warming — hotter air can hold more moisture, so when a storm gathers it can unleash massive amounts of snow. Colder air, by contrast, is drier; if we were in a truly vicious cold snap, like the one that occurred over much of the East Coast during parts of January, we would be unlikely to see heavy snowfall.
Well, that's very entertaining. While it's true that hotter air can hold more moisture, the comment about "a truly vicious cold snap" negates the argument. It disagrees with the weather records, too.

First, it negates the argument because it admits that a "truly vicious cold snap" existed even in 2010. Second, it tries to suggest that once upon a time, before the global warming began, there was nothing else than a "vicious cold snap" in D.C. in January and February.

That's, of course, a complete nonsense. Look at the climate profile of the U.S. capital. The average daily high in January is 42 °F (6 °C) and it is 47 °F (8 °C) in February. So it is surely not true that before the "catastrophic man-made global warming" began, the city was permanently suffering a "truly vicious cold snap".

Climate models are mentioned as another argument intended to show that snowstorms - and hurricanes - get bigger. Unfortunately, no reference is given so we can't look at this "argument". It's clear that even most climate modelers disagree with this proposition - and if their models show such a thing, they must know that it is an artifact of their being inaccurate. After all, if a hurricane is driven by the temperature differences, they should be reduced by AGW (poles are warming faster), so there should be less storminess.

But can't we see that the argument is "fundamentally" absurd, anyway? The problem is that the air that carries snow can't ever become terribly hot. There is some threshold near the freezing point that you simply can't exceed - otherwise the snow melts. Walsh is manifestly aware of this fact showing that his basic statement is ludicrous. So what does he say about this point?
But as far as winter storms go, shouldn't climate change make it too warm for snow to fall? Eventually that is likely to happen — but probably not for a while. In the meantime, warmer air could be supercharged with moisture and, as long as the temperature remains below 32° F, it will result in blizzards rather than drenching winter rainstorms.
So with global warming, the temperature is getting hotter, as he claimed previously, but it must still remain below the freezing point. Well, an average child would probably be able to figure out what's wrong with this combination of assumptions. If it is below the freezing point, it is not terribly hot, and consequently, the maximum amount of moisture in the air cannot be too high, either.

The bound for the maximum moisture is exactly equal to what it used to be when the world was colder but the global mean temperature was 0.6 °C lower than today. The maximum moisture of the air in D.C. only depends on the temperature in D.C., not on the global mean temperature, and Walsh's incoherent stuttering about the Greenland can't change it. A snowflake melts within minutes or seconds when the surrounding temperature is above the freezing point (or a nearby threshold): you can't fool the laws of physics, not even "for a while".

By the way, we have mentioned that the D.C. average daily mean temperatures are above the freezing point both in January in February. (Yes, even in the absence of the daily mean in the table, it's true because the average daily highs are more positive in degrees centigrade than the average daily lows are negative.) So an additional warming surely does mean fewer days when the temperature is below the freezing point - and fewer days when the temperature lies within any chosen interval of temperatures as long as the whole interval is below the freezing point. That's because the Gaussian curve decreases as you're getting further from the center - but I am sure that the normal people are capable to see this obvious fact without any maths, too.

When you look at his article carefully, you will see that there are no valid arguments, and those that are presented as arguments are completely wrong. So the proposition about "warming causing stronger snowing" is as wrong as you should have expected from the beginning. Warming obviously means less snow precipitation. I have estimated that a 1.5 °C warming in Prague would reduce snow roughly by 20 percent: such a change could occur in 100 years.

At the end, he realizes that no sane person is going to believe him, co he concedes that he had written just a pile of crap:
Ultimately, however, it's a mistake to use any one storm — or even a season's worth of storms — to disprove climate change (or to prove it; some environmentalists have wrongly tied the lack of snow in Vancouver, the site of the Winter Olympic Games, which begin this month, to global warming).
Note that it is surely a mistake to disprove "climate change" - but it is never such a mistake to prove it. Although he concedes that it was a mistake for him to prove "climate change" using the snowstorm in D.C., he only informs us about this mistake - which is actually relevant for the validity of his whole article - in parentheses while the opposite mistake is written as a main sentence.

Incidentally, Walsh mentions "environmentalists" who use the weather in Vancouver to support the AGW religion. In an e-mail he sent me today in the morning, Alexander Ač was victoriously celebrating a rainy and relatively mild weather in Vancouver and called for the whole olympic games to be canceled and declared a victim of global warming, I kid you not. ;-)

Of course, he wasn't interested in the basic Vancouver climate data showing that such conditions are pretty normal around Vancouver and that early February 2010 is just somewhat warmer than average - and still much cooler than years such as 1978 or 1998. Even the average daily low in Vancouver is above the freezing point - both in January and February. In all months, in fact.

For some people, the obsession with the unscientific concepts of a global warming doomsday is much stronger an addiction than heroine or cocaine. I am afraid that the only way to cure these people would be euthanasia - once done, they could be declared victims of the AGW (the religion). Of course, I don't want this to happen to poor AA, but I surely do think that he is genuinely sick.

And that's the memo.

1 comment:

  1. Water vapor is the major bone of contention between alarmists and skeptics. Alarmist see warming causing additional water vapor in the atmosphere, not in low lying clouds, but in high level clouds in the statosphere. According to their theory this then acts as a positive feedback to warm the planet more. Skeptics see low level clouds being formed which reflects radiation back into space and makes water vapor a negative feedback.

    So the warmists have to abandon at least part of their theory to say that this water vapor is accumulating as low level clouds and snow (precipitation). At the very least they are admitting they don't know how the water vapor reacts which greatly weakens the case for catastrophic AGW.