Wednesday, August 11, 2010

The Russia Thing

I am not sure how to take being definitely regarded as climate scientist by both Roger Pielke Jr (who is in and out of the Tobis-ooh-scary club) and Brad Johnson (a Romm protege), but not quite so definitively by anyone commonly regarded as a climate scientist. I suppose I should accept it as better than nothing. But Johnson's topic is worth following up. And I really liked that Brad got an actual meteorologist to back me up:
Like Dr. Tobis, Carver [Meteorologist Rob Carver, the Research and Development Scientist for Weather Underground] believes that manmade global warming has fundamentally altered weather patterns to produce the killer Russian heat wave. “Without contributions from anthropogenic climate change,” Carver said in an email interview with the Wonk Room, “I don’t think this event would have reached such extremes or even happened at all”:
I agree with Michael Tobis’s take at Only In It For the Gold that something systematic has changed to alter the global circulation and you’ll need a coupled atmosphere/ocean global model to understand what’s going on. My hunch is that a warming Arctic combined with sea-surface-temperature teleconnections altered the global circulation such that a blocking ridge formed over western Russia leading to the unprecedented drought/heat wave conditions. Without contributions from anthropogenic climate change, I don’t think this event would have reached such extremes or even happened at all. (You may quote me on that.)
Cool. Thanks for taking the heat, making a stronger claim than I did, Rob! And thanks for the work on this, Brad!

I want to explain my thinking in some detail on this, but I really don't have the time to do it justice right now. Of course it will be half-wittedly nitpicked and mocked to oblivion if I post it on a blog whether it's brilliant or foolish. I wonder if it rates a real paper somewhere. That would be a novelty...

But a short version occurs to me. Remember when I tried to explain that "global warming" and "anthropogenic climate change" don't mean exactly the same thing? Well, the fact that we now have situations like this one, and last year's in Australia, allows for making the point clear with some examples.

See, what we are worried about is not global warming. Global warming itself causes relatively little damage, at least at first. What we are worried about is climate change.

Anthropogenic global warming does not cause climate change.

Anthropogenic climate change causes global warming,.

Global warming (at the surface, just like global cooling in the stratosphere) is one of the more predictable symptoms of anthropogenic climate change. But if you change the forcing, you change the response. That's not a very deep scientific result, is it?

"Anthropogenic climate change" - well that's a tedious mouthful, isn't it? Not in a sense, no, not really. Not as tedious as what is happening this instant in Pakistan and in Russia, anyway. That's what abrupt climate change looks like.

Tuesday, August 10, 2010

Handy FIR filter inherits from list:


class filter(list):

"""real valued F I R filter with memory"""

def __init__(self, coeffs, data=None):
list.__init__([float(item) for item in coeffs])
if data:
assert len(data) == len(coeffs)
self.data =[float(datum) for datum in data]
else:
self.data = len(self) * [0.]

def __call__(self,value=0.):
return self.filter(value)

def output(self):
return sum(map(mul, self.coeffs, self.data))

def update(self,value):
self.pop(0)
self.append(value)

def filter(self, value=0.):
value = float(value)
self.update(value)
return self.output()

def innovate(self):
return self.filter(white())