Friday, April 23, 2010

Ray Pierrehumbert on the habitable zone


The habitable zone is the region about a star where an earth-like planet can exist. Ray Pierrehumbert is lecturing at the University of Toronto on New Worlds, New Climates and Steve Easterbrook has an excellent report. The figure to the left, stolen from Steve, who took it from Rockstrom et al, Nature 461, 472-475 (24 Sept 2009) shows the green zone for Earth like planets, the red is where we are. The news is not good

Thanks to Jim Eager for having FTFL to the lecture slides

Comments?

19 comments:

Anonymous said...

Still somewhat more optimistic than my view of the future. Whatever way you look at it we are so screwed.

Unfortunately the veneer of civilisation is very thin. I do not see how civilisation can cope with the changes ahead.

So; although the physical environment is going to change in ways that we do not like, the social changes will be more immediate and, for those alive now, far worse.

Rabid doomsaying little mouse.

JohnMashey said...

Minor nits:
<-left right->

Any change of tweaking the image or adding labels? the words in red are pretty tough on old eyes.

Jim Eager said...

Damn! This is the first I've heard that Ray was lecturing at UofT all this week. If I'd known I could have caught a few of them., especially the snowball earth talks. Oh well, at least the slides are available for downoading.

EliRabett said...

Well it's a bit better if you click on it, but the two red ones are biodiversity loss and nitrogen cycle.

Anonymous said...

I'm with Anonymouse @ #1 - we're forked. Even in the absence of climate change, the extant biodiversity loss (due to large-scale agriculture, resource extraction and just your general day-to-day development) may be enough to shift the responses of several key ecological indicators. I can only speculate on how things will look 20 years (let alone centuries) hence with 8+bn people all aspiring to the (much-vaunted but largely under-examined) Western "lifestyle". Almost the only aspect of guvmints getting involved in climate change that pi$$es me off is that it unfailingly means the amount and proportion of taxpayer $$$ devoted to stemming biodiversity loss is reduced.

Marsupial Mouse

bill said...

I don't think I'm going to be the only one raising eyebrows at the 'well within safe margins' designations for Change of Land Use and Fresh Water Use. As an Australian I'd say we blew those out here more than 2 decades ago...

guthrie said...

What I am seeing is that there are many people who dislike greens because they claim that they put everything else ahead of humans, but don't seem to fully grasp the dangers posed by all the changes in water supply, etc etc.
We need more information in the public sphere, and more study of the dangers and what will happen unless action is taken.
Can anyone point to some good ones?

Steve Easterbrook said...

Thanks for spotting that the slides have been posted! I've updated my post with the chart I most wanted from them...

Francis said...

As a resident of Southern California and someone who follows John Fleck's postings on the Colorado River (not to mention the ongoing wars over the Bay Delta), I feel that the freshwater redline needs to be on the far side of the green line. While California is not the world (even if we think it is), it is one of the largest global economies and is highly reliant on an already overtasked system.

birdbrainscan said...

I had the good fortune to be able to attend all five of Ray's talks, and to meet him at a reception as well. He is as gracious in person as he is eloquent in writing. Watch for his forthcoming textbook on planetary atmospheres - i found the preview galleys highly readable and engaging back when they could still be posted on his website (the one downside to the book going to press is you can't leave the previews up - but the book should be well received based on what I got to see.)

What really struck me about Ray's talks was his deep interest in pure science for its own interest. While he is a climate activist, he clearly shows he would rather just be figuring out which distant planets may lie in the "Goldilocks zone", and refining the definition of what makes for a habitable planet.

Earth Day fell on the Thursday of that week, and Ray used his talk that day (#4) to address climate justice and ethics. If you want his take on those, the fourth PPT should get you there. (Thanks for the link to the PPTs - I'll go back and review these later.) Short version: "short wave" geoengineering, i.e. reducing solar input via stratospheric injection of sulphates, is simply unethical. The big objection is the burden of keeping it going, as the residence time is under two years, while the CO2 buildup will last for centuries. He is more upbeat about "long wave" geoengineering, i.e. ways to draw down CO2 already in the air, whether "artificial tress", biochar, or CCS from biomass-fired power generation (he did not go into specifics, except to note the latter two options during the Q&A.) His focus was that future technology developments could yield workable means of free air capture of CO2 for sequestration, and that could offset the "last gigaton per year" of carbon emissions that he sees as the hardest to eliminate.

Jim Prall

P.S. Jim Eager - I don't think we've met; if you're even on UofT campus, please look me up. Google my name and the top hit is my homepage including campus tel. and office.

chris said...

Jim Prall, I notice on your website (list of skeptics and their admirable publication records) that you have Christopher "sane-and-sensible" Monckton listed as "Sir Christo..".

That's really going too far! Mr Monck hasn't done anything remotely deserving of Sir-ship. He hasn't managed even one top-ten single (unlike Sir Paul McCartney); and of course, he's not a member of the House of Lords..

however he is "a qualified Day Skipper with the Royal Yachting Association", and perhaps that's reason enough for taking his ("sane and sensible") veiws on climate science seriously...

Horatio Algeranon said...

He [Mocktman] hasn't managed even one top-ten single (unlike Sir Paul McCartney)

Perhaps not, but his lardship has a song written about him, which should count for something.

David B. Benson said...

Having a lordhsip is not a qualifiaction for the title of sir; being knighted is the only way.

And, by the way, the designation is Sir Paul for Paul McCartney. Family names are never used with that (earned) title.

Steve Bloom said...

David, dipping deep into the obscure, there are also the numerous heriditary baronets and the singular Green Knight, all designated Sir (or Dame).

Horatio Algeranon said...

Related to both the above graphic and knighthood:

Watch Steven Hawking (who was offered knighthood, but turned it down) reply to Charlie Rose when asked "What are we not doing to prevent these [man-made] disasters that we absolutely should be doing?"

David B. Benson said...

Steve Bloom --- The Green Knight is of course a knight.but those baronets are certainly deeply obscure.

Thanks.

Anonymous said...

Bunny fun, I guess?... Let me see if I unterstand the situation here? You silly rabbits are looking to find out the perfect place for you all to nest with(& I must say, you Do look cute in her arms Mr. Rabbit:) your favorite greenery.) you can see that her dad don't smoke because you got a big glass to look through and see but isn't that solar system just a few, as you all see things anyway; light years away at least?... How much time at light speed, as a percentage, to get you all there? What a picture. She is gonna be dead before you can get there; right? What is the rush when 'she' is right under me? You could see hare next and then give hare a call... How much does it cost us to move objects at light-speed; Eli? You all live too close to the ground to see very far, that has got to be your problem today. Climb a tree rabbits! More time too; Flap on, Bye-Bye

Antiquated Tory said...

I have to say, this time ranting flappy drive-by regular anony has managed to make no sense whatsoever. I'm really not sure how commenting that other habitable solar systems are beyond reach in any way discredits a post on how we are making our current planet inhospitable. On the contrary, it would seem to support it.

Hank Roberts said...

speaking of habitable zones, note the wet-bulb-thermometer story from PNAS
http://www.pnas.org/content/early/2010/04/26/0913352107.full.pdf
that's going to be in the news right about ... now .... may be reminiscent of, erm, this one from E'n'E:
http://filebox.vt.edu/artsci/geology/mclean/Dinosaur_Volcano_Extinction/pages/grhskill.html