2010-08-27 08:51:39Species shift: Moving climate zones
nealjking

nealjking@gmail...
91.33.114.71

mothingate,

The following is too long for a single post, but I think of it as a single story. Maybe you can consider how it can be broken up and restructured, in light of other articles you have planned.

Neal

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

 

Over the last 100 years, the Earth has warmed about 1° C, or at about the rate of 0.1° C per decade. That doesn’t seem like very much, considering that the temperature can vary by more than 30° C in a single day. However, average temperature is an important parameter of climate, determining where flora and fauna can, or cannot, survive.

 

Let’s consider that 0.1° C warming over a ten-year period. If you were sensitive to that warming, and decided to move poleward to compensate, how far would you have to go? Well, the average temperature (at sea level) drops about 67° C over the 10,000 km distance from equator to pole, so that implies that a 1° C change can be compensated by traveling about 150 km; a 0.1° C change by a 15 km trip.

 

Or, another direction you could take: Instead of trekking poleward, you could hike upwards. For well understood reasons, the temperature of dry air drops with altitude at the rate of about 10° C per km, or 0.1° C in 10 m; humid air more slowly.

 

So, if you wanted to, you could compensate for the slow rate of global warming by moving 15 km every decade, or climbing another 10 m to higher territory. There’s just one problem: If you’re a tree, you can’t do that.

 

If you’re an animal that lives among trees, you can’t just leave them. Still stuck.

 

If you take a longer view, and focus on the forest instead of the trees, it’s still hard to believe a forest can extend itself at a rate of 15 km per decade; and when trying to climb up 10 m, it needs convenient topography: not too flat and not too steep. The accidents of geography (a shore, a mountain) can block the path, as well as the human facts on the ground: roads and cities.

 

So there’s nothing for it but to adapt. Flora and fauna have adapted to temperature change before, haven’t they? Yes; but the timescale for previous changes have been on the order of 100,000 years or even much more, and now we are talking about perhaps 200 years for equivalent temperature change. It is wildly optimistic to think that most species will be able to evolve around this shock; it is much more plausible that they will die out without descendants.

 

Indeed, many biologists refer to the current period as the “Holocene extinction”, in which we are losing species at an alarming rate, due to the human impact on the biosphere (including global warming). The biologist E.O. Wilson estimates that half of all species could disappear by 2100.

 

The halving of our genetic inheritance is not solely a problem for the species that go. A biosphere rich in species must have a great deal more flexibility in dealing with accidents and catastrophes than one with a small number. Over the period during which humanity will be inhabiting this planet, we do not know what disruptions may occur: The more robust it is, the better it will be for us.

 

2010-08-27 15:32:52
mothincarnate

wow.the.moth@gmail...
192.43.227.18

lol, I didn't see your title on the other page so missed this!

Pretty good, technical too :)

I'd suggest:

"There’s just one problem: If you’re a tree, you can’t do that." -> "There’s just one problem: If you’re a tree, you can’t use either option."

"If you take a longer view, and focus on the forest instead of the trees, it’s still hard to believe a forest can extend itself at a rate of 15 km per decade; and when trying to climb up 10 m, it needs convenient topography: not too flat and not too steep. The accidents of geography (a shore, a mountain) can block the path, as well as the human facts on the ground: roads and cities."

->

"If you take a longer view, and focus on the forest instead of the trees, it’s still hard to believe a forest can extend itself at a rate of 15 km per decade; and when trying to climb up 10 m, it needs convenient (and therefore unlikely) topography: not too flat and not too steep. The accidents of geography, both natural, such as mountain ranges and water barriers, and human changes to landscape use, such as cities, agricultural plots and even roads."

I will be discussing early indications of adaptation, which might slightly contradict the next paragraph (but trust me, not by much really), so that and the next paragraph (which is a really good point) might be condensed a little.

Excellent summing up as well - it follows on well from the first post idea, discussing the importance of rich biodiversity for resilience.

Hopefully we can get John's feed back (I know he is thinking of a physical series to compliment, so it would be useful in this way to get his input) - I'd like this to be the second post, which will assist the first for setting the scene for the cast studies.

2010-08-27 18:45:20Revised version: The hitch-hiking tree: AGW and the shifting climate zones
nealjking

nealjking@gmail...
84.151.44.130

Over the last 100 years, the Earth has warmed about 1° C, or at about the rate of 0.1° C per decade. That doesn’t seem like very much, considering that the temperature can vary by more than 30° C in a single day. However, average temperature is an important parameter of climate, determining where flora and fauna can, or cannot, survive.

 

Let’s consider that 0.1° C warming over a ten-year period. If you were sensitive to that warming, and decided to move poleward to compensate, how far would you have to go? Well, the average temperature (at sea level) drops about 67° C over the 10,000 km distance from equator to pole, so that implies that a 1° C change can be compensated by traveling about 150 km; a 0.1° C change by a 15 km trip.

 

Or, another direction you could take: Instead of trekking poleward, you could hike upwards. For well understood reasons, the temperature of dry air drops with altitude at the rate of about 10° C per km, or 0.1° C in 10 m; humid air more slowly.

 

So, if you wanted to, you could compensate for the slow rate of global warming by moving 15 km every decade, or climbing another 10 m to higher territory. There’s just one problem: If you’re a tree, you can’t do either.

 

If you’re an animal that lives among trees, you can’t just leave them. Still stuck.

 

If you take a longer view, and focus on the forest instead of the trees, it’s still hard to believe a forest can extend itself at a rate of 15 km per decade; and when trying to climb up 10 m, it needs inconveniently unlikely topography: not too flat and not too steep. Accidents of geography (a shore, a mountain) can block the path, as can the human impact on the landscape: cities, agricultural plots and even roads.

 

So there's nothing for it, but the forests and fauna will have to adapt. Is that likely, given the time frame of about 200 years? That will be discussed in another article in this series, but the bottom line is: It is wildly optimistic to expect that most species will be able to evolve around what we should more properly regard as a temperature shock than as a gentle rise. It is much more plausible that many will die out without descendants.

 

The impoverishment of our genetic inheritance is not solely a problem for the species that go. A biosphere rich in species has a great deal more flexibility in dealing with accidents and catastrophes than one with a small number. Over the period during which humanity will be inhabiting this planet, we do not know what disruptions may occur: The more robust it is, the better it will be for us.

2010-08-27 19:14:07Which rebuttal?
gpwayne
Graham Wayne
graham@gpwayne...
217.44.86.17

Which argument is this a rebuttal to?

It would help if authors would follow the naming convention for the thread title (the title is that of the first post in the thread, and can be edited by the author).

2010-08-27 19:45:12Not a rebuttal (I think)
BaerbelW

baerbel-for-350@email...
109.85.9.128

Hi Graham,

not sure if Neal and Tim are around to answer your question, but I think that this thread is not meant as a draft to a specific rebuttal. Instead it is part of a new series related to this thread Tim started recently about ecological repurcussions of climate change.(Tim, Neal, please correct me if I'm wrong)

This does however highlight the need for s.th. I suggested a while ago: it would help to have sub-forums to eg. keep work on basic-rebuttals separate from work on new blog-posts or even new series like this one.

Cheers
Baerbel

 

2010-08-27 20:58:07BaerbelW: You're right
nealjking

nealjking@gmail...
84.151.44.130

Yes, it's not a rebuttal, but a post for a series.

Either a separate forum or a new naming convention would help.

2010-08-28 11:47:57Take it with a grain of salt...
doug_bostrom

dbostrom@clearwire...
184.77.83.151

Coming from me, that is, but this is not too long at all and I think it's an excellent topic for a general blog post.

Somewhere I've seen a map showing climate regime movement by latitude. Trying to think where...

2010-08-29 17:26:49Animated hardiness zone map.
villabolo

villabolo@yahoo...
76.93.65.8

Neal. Here's an animated hardiness zone map that may be of help. I think this may be what doug is referring to.

http://www.arborday.org/media/mapchanges.cfm

VILLABOLO

2010-08-29 19:44:11Useful animation
nealjking

nealjking@gmail...
84.151.45.10

villabolo,

 

The animation looks good. What is the http command to incorporate it? Or is it better just to link to it?

2010-08-30 08:07:48
mothincarnate

wow.the.moth@gmail...
118.210.183.39

That arbor flash pres is a great one huh? It'll be helpful for the reader to understand the reality of this piece. Maybe a screen grab by it would also be useful.

Hi Graham, BaerbelW is correct - I also have Part 1 on Species Shifts on a post here too (this one is to be the second post after which we use case studies - 1 or 2 papers - to explain focused examples of change underway or likely to occur to help bring home just how damaging climate change is to ecology.