What's old is new once again. I'd actually written most of this in February, when Heartland was in the news. But between one thing and another, hadn't posted it. Now that they're in the news again, it seems once again to be apt. As usual, my interest is on the science. Since a number of Heartland supporters are saying things in the vein of Heartland made a misstep in acting as they did, because it takes away from their message on the science. The supporters think Heartland is doing well on the science.
Now that I've looked in to what Heartland Institute has had to say on sea ice, I can say with confidence that they are not doing well on the science. They don't know (or lie about) the difference between ice area and ice extent, don't know how much area of ice there is, don't know where it forms, make up numbers even if you ignore the difference between area and extent, lie about what authors say in their scientific papers, treat 2 years as plenty for establishing a climate trend if it is in one direction, but ignore the 30 year trends when it isn't, don't know the difference between sea ice and ice shelves, don't understand how sea level changes, and others I'll let you classify yourself.
The gory details, examples being from their web site, are below the fold. A different point is, I don't expect everyone to be expert on sea ice, or even pay attention to it. If Heartland had ignored sea ice, that's fine (at least it is if they're not saying things which require understanding sea ice). But they chose to write about it. And the people whose articles I'm quoting are Jay Lehr, their science director, and James M. Taylor, a senior fellow for the Heartland Institute focusing on environmental issues. In other words, major players in deciding what Heartland says about science, not someone who might once have said something stupid about sea ice while passing through the office.
Having done my homework, I'm comfortable in saying that Jay Lehr and James M. Taylor are unreliable sources on the science, and Heartland Institute is as well. See below for my homework example.
07 May 2012
18 April 2012
In the mean time ...
I will indeed be getting back to the simplest climate model, including that comment from Nick Barnes that got clobbered by my fingers being fatter than my smartphone buttons. (Deleted rather than approved message, fortunately I still have it in email.)
While waiting for that, some video suggested by Hank Roberts in a comment a fair while back (December 9th, 2011):
AGU is the American Geophysical Union. I was surprised when, a while back, someone congratulated me on my 25 years as a member. They do some good work there. I just didn't realize that I was that old.
Different recommendations, also from Hank:
During the multitudinous-record-setting month of March (for the US, at least) anonymous mentioned http://www.wunderground.com/climate/extremes.asp, which is a nice place to check out record temperatures and precipitation.
In a different mean time matter, I am starting to take http://penguindreams.wordpress.com/ live. There is much sawing and hammering still to do, but there are also a couple of real posts there already. My plan has always been for that blog to be the place where I don't restrain my use of math and scientific language. Questions are still, as always, welcome, including on that scientific language. If you don't have an intuitive idea already of what a Rossby radius is, do ask. Just that over there, I won't examine my language for such terms and go for verbal instead of mathematical descriptions. For those who'd like to get more in to guts of the science, a la scienceofdoom, that'll be the more apt place. If you think this blog is already scarily mathematical, that place might best be one to leave to other readers. The most recent note there is nonmathematical, just promises (threatens?) math to come. No plans to abandon this one. Just that sometimes things come up, such as Nick's questions/comments, where it would be easier to just whip out the mathematics straight off.
Also, now that I'm catching back up here (partial blame to my son who introduced me to World of Warcraft :-), there are answers showing up to long-asked questions. Or at least responses. Please check the 'recent comments' links below for yours Jacob.
While waiting for that, some video suggested by Hank Roberts in a comment a fair while back (December 9th, 2011):
Recommending -- from the AGU videos, Ben Santer on Steve Schneider.
He begins with a memorial -- Steve Schneider is part of history.
He goes on to a teaching story.
http://vimeo.com/33387515
CG43G : AGU Fall Meeting 2011
AGU is the American Geophysical Union. I was surprised when, a while back, someone congratulated me on my 25 years as a member. They do some good work there. I just didn't realize that I was that old.
Different recommendations, also from Hank:
http://www.skepticalscience.com/pics/MSU_cherries.gif might be a nice illustration for your discussion of results on deciding trends; it's from http://www.skepticalscience.com/news.php?p=3&t=130&&n=1005
Also a re-recommendation of the very cool slider graph tool here -- page down to get to it:
http://sciblogs.co.nz/hot-topic/2009/10/20/%E2%80%A6keep-out-of-the-kitchen/
During the multitudinous-record-setting month of March (for the US, at least) anonymous mentioned http://www.wunderground.com/climate/extremes.asp, which is a nice place to check out record temperatures and precipitation.
In a different mean time matter, I am starting to take http://penguindreams.wordpress.com/ live. There is much sawing and hammering still to do, but there are also a couple of real posts there already. My plan has always been for that blog to be the place where I don't restrain my use of math and scientific language. Questions are still, as always, welcome, including on that scientific language. If you don't have an intuitive idea already of what a Rossby radius is, do ask. Just that over there, I won't examine my language for such terms and go for verbal instead of mathematical descriptions. For those who'd like to get more in to guts of the science, a la scienceofdoom, that'll be the more apt place. If you think this blog is already scarily mathematical, that place might best be one to leave to other readers. The most recent note there is nonmathematical, just promises (threatens?) math to come. No plans to abandon this one. Just that sometimes things come up, such as Nick's questions/comments, where it would be easier to just whip out the mathematics straight off.
Also, now that I'm catching back up here (partial blame to my son who introduced me to World of Warcraft :-), there are answers showing up to long-asked questions. Or at least responses. Please check the 'recent comments' links below for yours Jacob.
22 March 2012
Technical followup on the simplest climate model
Tuesday I took up reconsidering the simplest climate model. This time, I'm trying to get rid of the annoying bit of having to know the planet's albedo (reflectivity) in order to find its temperature. Instead, to have some fundamental relationship between temperature and albedo, so that everything in the model is either a fundamental constant (the Stefan-Boltzmann constant), or a fundamental principle (black body radiation, this new albedo-temperature relationship). No great surprise that some readers have already caught on to some of the issues I wanted to talk about.
One, which I'll continue to defer for now, is the fact Arthur mentioned that what this model works with is the earth's blackbody temperature -- its temperature as seen by how much energy it releases to space -- rather than surface temperature. Since we all live somewhere towards the surface, surface temperature is the more interesting number. What the difference between what the model can give us and what we're truly interested in does is to suggest that an important theoretical issue is to develop an understanding of how planetary blackbody temperature relates to surface temperature. Or (scarier) to see if it does relate in any consistent way. But heads up that such a discussion will be coming. Finding these issues, and seeing why they're important, is one of the purposes of the ultra simple models like this.
More issues were brought up by Nick Barnes, who also provides Python code for running your own version (see his first comment for that link). I hope you've spent some time with either the spreadsheet or Nick's Python (use a 2.7 set-up, per Nick's comment on Tuesday) or do so now, as you read this post, and some more as you decide whether and how it makes sense. The spreadsheet is in OpenOffice format (.ods) but I've opened that with MS Excel previously. If you can't, please let me know.
Now, in saying 'issues', I don't mean that there's any terrible comment being made. Rather, it is the truth that even very simple models like this one have some subtleties that you should explore before drawing your conclusions about nature. I'll take up the more physical side of interpretation next, but first let's take a look at some of the technical issues.
One, which I'll continue to defer for now, is the fact Arthur mentioned that what this model works with is the earth's blackbody temperature -- its temperature as seen by how much energy it releases to space -- rather than surface temperature. Since we all live somewhere towards the surface, surface temperature is the more interesting number. What the difference between what the model can give us and what we're truly interested in does is to suggest that an important theoretical issue is to develop an understanding of how planetary blackbody temperature relates to surface temperature. Or (scarier) to see if it does relate in any consistent way. But heads up that such a discussion will be coming. Finding these issues, and seeing why they're important, is one of the purposes of the ultra simple models like this.
More issues were brought up by Nick Barnes, who also provides Python code for running your own version (see his first comment for that link). I hope you've spent some time with either the spreadsheet or Nick's Python (use a 2.7 set-up, per Nick's comment on Tuesday) or do so now, as you read this post, and some more as you decide whether and how it makes sense. The spreadsheet is in OpenOffice format (.ods) but I've opened that with MS Excel previously. If you can't, please let me know.
Now, in saying 'issues', I don't mean that there's any terrible comment being made. Rather, it is the truth that even very simple models like this one have some subtleties that you should explore before drawing your conclusions about nature. I'll take up the more physical side of interpretation next, but first let's take a look at some of the technical issues.
20 March 2012
Return of the simplest climate model
The simplest climate model balances the energy leaving the earth to space with the energy coming in from the sun. If the climate is not changing, these two will be the equal. As long as climate is not changing rapidly, a modifier we can make quantitative, they'll be very nearly equal. It turns out that even for fairly rapid climate changes, by standards of geological history, the earth is very close to that balance.
I'm actually going to take a different approach this time around. Key to deciding how much solar energy comes in to the earth (more precisely, the climate system) is knowing the albedo -- what fraction of incoming energy gets bounced right back out. That makes the model unsatisfactory to me on a theoretical basis. We have to know the earth's albedo to compute its blackbody temperature (the temperature which provides that balance). The problem with that is that the albedo itself is a climate term. The state of the climate -- how many clouds we have, how large the sea ice pack is, how large the continental ice sheets and deserts are, how green the forests are -- determines the albedo. Knowing either the blackbody temperature or the albedo is a climate observation. Given one, we can compute the other from that simple model. And, which is a good point, we can compare our computed temperature with the observed.
Is it possible to remove or weaken that restriction on the albedo? And if so, can we learn anything about the climate system? Yes, and yes.
I'll do something that would be quite improper if I were to claim that it was exactly true, but which will turn out to be extremely educational. Namely, I will make up a relationship between albedo and earth's blackbody temperature.
I'm actually going to take a different approach this time around. Key to deciding how much solar energy comes in to the earth (more precisely, the climate system) is knowing the albedo -- what fraction of incoming energy gets bounced right back out. That makes the model unsatisfactory to me on a theoretical basis. We have to know the earth's albedo to compute its blackbody temperature (the temperature which provides that balance). The problem with that is that the albedo itself is a climate term. The state of the climate -- how many clouds we have, how large the sea ice pack is, how large the continental ice sheets and deserts are, how green the forests are -- determines the albedo. Knowing either the blackbody temperature or the albedo is a climate observation. Given one, we can compute the other from that simple model. And, which is a good point, we can compare our computed temperature with the observed.
Is it possible to remove or weaken that restriction on the albedo? And if so, can we learn anything about the climate system? Yes, and yes.
I'll do something that would be quite improper if I were to claim that it was exactly true, but which will turn out to be extremely educational. Namely, I will make up a relationship between albedo and earth's blackbody temperature.
19 March 2012
Tempest in an ice pot
There's a bit of a tempest at WUWT and Steven Goddard's regarding satellite data on sea ice. And there are some anxious comments about FOIA filings to be made regarding data that's been hidden. I have to concede that it takes a bit of a historian to know what's really being said in the IPCC first report regarding sea ice. (see page 224, figure 7.20 for the source of the tempest.) Fortunately, I am such a historian :-) To give away the ending: There's nothing terribly dramatic going on in the sea ice or the history. But I'll take the chance to talk history of sea ice analysis.
The tempest arises because the figure shown there has sea ice cover in the early 1970s in the Arctic being notably lower than it was through the 1980s. (Curiously, no interest is displayed at either site regarding the Antarctic being far higher in the 1970s than the 1980s.) If the figures were commensurate with the satellite observations such as those used in the Cryosphere Today anomaly figures, it would suggest that the Arctic coverage of the last few years wasn't as remarkable as we've generally thought. (On the other hand, it would also say that the 'record high' Antarctic coverage of recent years was not particularly high at all, a point being neglected at both sites.)
The tempest arises because the figure shown there has sea ice cover in the early 1970s in the Arctic being notably lower than it was through the 1980s. (Curiously, no interest is displayed at either site regarding the Antarctic being far higher in the 1970s than the 1980s.) If the figures were commensurate with the satellite observations such as those used in the Cryosphere Today anomaly figures, it would suggest that the Arctic coverage of the last few years wasn't as remarkable as we've generally thought. (On the other hand, it would also say that the 'record high' Antarctic coverage of recent years was not particularly high at all, a point being neglected at both sites.)
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