Thanks!

Well, I’ve got some good news and I’ve got some bad news ;-)

There will be crops north of 30, just mostly on the West Coast. Short growing seasons are not so hard. There are many short season varieties developed specifically for cold northern climates. For any given latitude, you can also just grow a slightly more cold tolerant crop (i.e. Kale instead of Chard or Potato instead of Wheat). And if you are willing to put together cloches or greenhouses, there is no limit.

Per the “imminent” ice ages: WHEN it starts (that could be up to 10,000s of years in the future, but also could have been back in the LIA) it will proceed slowly. I figured it out at about an 800 foot per year rate of ice advance… It will be very hard to know when it has happened because we are about 3 or 4 orders of magnitude off in our sense of time vs glacial time.

Mitigation? Probably not so hard. One solution I saw proposed was to just widen the Panama canal to a few miles with “Atoms for Peace” excavation and restore the current that used to keep them away. Another would be to just make lots and lots of Freon again… and there are always the space mirror concepts. Personally, I’d just by a Polaris snowmobile…

Bottom line is that if a brand new Ice Age Glacial Period had started 200 years ago, we would know for sure in about 2000 years. Nuclear power is effectively unlimited, and with that you can have unlimited greenhouse foods and heat. So we might all end up living in Brazil in condo’s. I’m good with that ;-)

Thanks Richard, that’s very kind of you. Much appreciated.

And if Anthony finds the time to send it through/post it up, also much appreciated!

The use of invertebrates/invertebrate structures for this kind of analysis is fascinating (to me, at least!).

Many thanks

Mike

http://earthobservatory.nasa.gov/Features/Milankovitch/milankovitch_2.php

I now have a pdf made from scanning the journal article

I can’t work out how to attach it here.

I’ve emailed it to Anthony to either post on WUWT or to email you directly.

Richard

These are not tipping point, per se. All systems are inherently unstable unless they have some stabilisers built in (feedback). You will have heard sound systems that suddenly scream a very loud monotonic sound normally due to positive feedback from microphone to speaker and back again and so on. This is positive feedback. You may have seen someone adjust the volume so as to eliminate this whistle, that is reducing the positive feedback. Thge point at which it begins to screech could be termed a tipping point. In all large systems this is usually the end game and the system runs away to destruction. Chenobyl was a classic example. The carbon rods were designed to block the neutrons which were the positive feedback to the nuclear reaction but they failed to bring enough blocking to restrain the neutrons and voilà disaster ensued.

There is little evidence for these dramatically rapid tipping points in our climate system, not because they don’t exist because they almost certainly do, but because in 3000,000,000 years climate change had been within nomminally reasonable bounds in spite of some massive changes caused by asteroids etc. That is, we have much the same climate now as we probably had some 10,000,000 yrs ago. The climate has swung between ice ages and period of greater warmth than now and the climate of now is not the climate that can be said to be NORMAL but never the less you have to admit that it is fairly stable +/- 0.5 °C in 150 yrs considerable humankind’ nasty habits.

Ergo, somewhere in this massive system there has to be a good balance between negative and positive feedback which cannot be easily tipped either way very easily. Remember, in the last 250 yrs there have been some pretty big volcanic eruptions which temporarily modified the climate but the climate always returned to it’s previous state. This in itself is good evidence for some sizeable negative feedback(s).

I am becoming concerned about the data for hypothesizing about “abrupt climate change” or even “flickers”. (I have been reading abstracts of a number of recent studies.) How is the data being gathered and for what purposes? Is this topic coming more to the forefront today in order to scare us further about “tipping points” due to the combination (now it’s usually a combination) of forcing elements that always include CO2?

Will the 2009 International Conference on Climate Change March 8-10 begin a list of vetted data gatherers (in addition to the presenters), and scientists whose research is based on valid data, and organizations who only work with valid data or who rush to correct theirs when problems are found? Our universities can no longer be trusted nor can our government scientists. IMO this is an important function for the only independent and investigative center in our society — serious bloggers.

Well that’s a far-out theory. A supergalactic wave? Huge CMEs from the sun reaching the earth’s surface causing firestorms?

Very interesting at least. It does explain the lack of craters. Kinda scary to think that galactic “weather” could cause that kind of havoc so recently.

This is the general thesis about the appropriate means of statistical analysis to use, given the properties of the geophysical time series.

I refer readers to the homepage of Demetris Koutsoyiannis who has got across this problem probably better than anyone else in the world (see http://www.itia.ntua.gr/dk/).

There is a month of Sundays of hard work to understand properly the remarkable scholarship listed there.

Also Demetris’ pioneering breakthoughs have been recognised by his peers: he is awarded the Henry Darcy Medal for Hydrological Sciences at the forthcoming EGU2009 in Vienna.

Read the Abstract of his lecture here:
http://meetingorganizer.copernicus.org/EGU2009/EGU2009-14033.pdf

It promises some very exciting intellectual breakthroughs central to the issue under discussion here, indeed central to our understanding of geophysical time series (of which climate time series are a subset) and economic and finacial time series such as those that tried to tell us of the impending GFC but “we” (ie the government and financial sector orthodox econmetric analysts weren’t using the right tools so we couldn’t hear the screams of warning.
Richard

It’s Sunday evening down here in the land of Oz. I’ll be in the office during the week and will do my best. I have the journal so it shouldn’t be too hard!!

Richard

”we need 2-3 centuries of measurements to tell if it is indeed climate.”

That is also the lesson taught to us by the efforts to allocate stream flows based on 30 year average precipitation. Proper allocation of available historical stream flow over 30 years will leave some water claims unsatisfied in a subsequent 30 year cycle.

This is one of the reasons California is having water supply problems, she has been using more then her allocation of water for Colorado river water for some time. It was not a problem when Arizona and Nevada did not use their full claim, but as the upstream states begin to claim more of their allowed water usage California is getting left short. The Colorado River compact was drawn up in 1922 with water usage limits predicated on what they believed to be reasonably expected average flow of the river system. Over the years it has been found that the total flow in the river system has a wider swing than they anticipated, and growth has also exceeded expectations. Precipitation like temperature can vary over wide ranges over century time spans as the Anasazi found out.

http://wwa.colorado.edu/colorado_river/docs/CO%20River%20Compact.pdf

http://wwa.colorado.edu/colorado_river/docs/pontius%20colorado.pdf

The wettest 10-year period on record (1914 to 1923)
saw an average annual flow of 18.8 maf. This period is especially significant because the Colorado River Compact, which allocated the river’s water, was
negotiated in 1922. Since 1922, estimates of the river’s average flow have been
consistently revised downward.

We have already learned that short time span averages are inadequate for water management, it should not be surprising that similar short time spans do not get the job done when talking about temperature or sea level trends either.

Larry