Norwegians trying to act like nothing's wrong while Global Warming ruins their day!

Ah the new nordic olympic sport :)

Just when I began thinking you're opinion is mostly correct, you came up with this. Really? Are you kidding me and everybody else reading scienceblogs.com? It is embarassing that it appeared on the "Physicial Science" page, where people blog having a good style of writing, explaining complicated things about particle physics (like Ethan) in a interesting way, etc. etc... But honestly, you must be joking...

I'm a Masters student in physics, therefore I really had to learn what science means. But claiming "Norwegians get their days ruined by Global Warming", that is ridicilious. Where is your data for that? Nobody supports this thesis, and actually nobody has ever made such a statement. Give me a paper claiming "Norwegian storms in inner cities are getting stronger" and I WILL support your statement.

First, get a sense of humor or move one. Second, yes, storms are worse now than they were decades ago because of increased energy in the atmosphere. Physics predicts that, meteorology measures that. Third, there is a significant qualitative shift over the last few years in the jet streams' configuration and effects on storms. I've written about that extensively, just look up thread for several items.

I love the "I used to think you were great then you said this thing that never occurred to me so now I'm pissed off" trolling. When combined with the "you don't belong on science blogs" trope it is priceless.

Matthias, the only comments you have ever made on this blog are rather anti-science. Maybe you did not get to the "science" part of your Masters studies!

Well, I didn't think saying storms are universally enhanced by global warming was correct. We are getting effects, such as an increasing erratic jetstream that seems to be associated with lower polar/tropics temperature differences. But, still as always the vast bulk of modern storms are weak ones, it is the tail of the distribution that matters here, not the average run of the mill weather system. So next time please drop the universality claim.

Its more complicated than 'more energy in the atmosphere equals stronger storms'. Storms are driven by atmospheric density differences, not by the overall thermal content of the air. True we have more working fluid (atmospheric moisture), but thats only up a four or five percent, and the difference from say fifty years ago is far less than the seasonal variation at temperate latitudes. So the increase in wild weather on a warming planet isn't intuitively obvious, it is due to subtle effects that climatologists are struggling to come to grips with.

It is impossible to remove the effects of a fundamentally changed atmospheric chemistry from what the atmosphere is doing. So it is correct. Yes, the severe tail of the distribution does matter when considering severity of storms. These two things are not in conflict with each other.

The overall thermal content of the air actually drives, in part, density differences. Four or five percent is a HUGE number at the tail end of the distribution. The increase of wild weather on a warming planet is intuitively obvious. But yes, it is complicated.

Greg, I don't see the obvious part of it. Extratropical storms are driven by temperature differences, which are lower with warmer polar regions. So the simple intuitive result would be weaker storms. Thats not what we are seeing, but it is what a simple mental model would expect.

Instead we are seeing a weaker but more meandering jetstream, allowing streams of air to move further north or south than used to be the case. This causes larger local gradients.

Consider just the US for a moment. Severe storms here include thunderstorm cells and tornadoes, which I'll group as one big thing with a lot of internal variation, which emerge in the mid to late spring and are a factor into mid summer. The source of energy and moisture for many of these storms is the Gulf, which with global warming caused increases in SST is warmer and provides both more energy and more moisture .

Tropical storms including hurricanes in the Atlantic and Pacific are probably more frequent, the stronger ones stronger, and among these, more readily fed with deeper warm temperatures causing larger storms to be even larger as hapened with Katrina and Haiyan, a phenomenon we can expect to become fairly common given the warming oceans.

Those are two examples of global warming directly contributing to greater storminess.

The shift in jet stream patterns caused by the change in gradient to which you refer causes greater north and south migration of air masses, as you suggest, and larger gradients; it also causes more blocking. Blocking can cause rainfall (enhanced because of warming causing more evaporation as you acknowledge earlier) to happen in compressed space. That rainfall that caused the colorado flooding this year should have been spread across a much larger region but was not because of blocking and 20 years ago would have been less wet (because of evaporation).

The only thing about all this that could be thought of as having been less obvious at one time because of a lack of data to feed into the models is the Arctic Amplification effects on jet stream dynamics, since the Arctic seems to have warmed faster and to a greater degree than people may have been expecting a decade ago. The rest of it is expected, and obvious.

There are some less obvious, more unknown things. The exact nature of changes in wind patterns affecting storm formation is not fully understood yet. I don't think we totally get changes in seasonality of stormy periods, but that they might length or shift isn't especially surprising.

I am in frequent communication with both meteorologists and climate scientists and they do not say what you are saying about what is obvious or unexpected, for the most part.

"The increase of wild weather on a warming planet is intuitively obvious."

And that's exactly the problem with making easily skewered statements implying that global warming is somehow responsible. Humor aside, this is Science, yes? If so, either we have evidence or we don't. We certainly have evidence that deniers as a group lack humor - why give them ammunition?

GregH, what is the point of ignoring thousands of words of writing on the topic by dozens of individuals?

I’m a Masters student in physics, therefore I really had to learn what science means.

The second statement does not follow from the first - look at the people with degrees in science who deny evolution, relativity, and (like you) climate change. Mastering mechanics does not equal understanding.

Here's something new on tropical storms: http://www.motherjones.com/blue-marble/2013/12/signal-increasing-hurric…

Omega Centauri, the temperature difference between the equator and the poles depends on the convective transport of heat by the atmosphere from the equator to the poles.

If there is a reduced temperature difference, then there is increased convective transport. That convective transport is also known as "wind", so reduced temperature differences implies increased wind.