I couldn't resist, even though I'll be long gone, fertilizing these warm crops.

http://www.usatoday.com/weather/climate/globalwarming/2009-01-08-climatechange_N.htm?csp=34

The counter claim is the data is flawed, but an interesting topic?

I don't know about overheating and 2100, but I know that this year in CA, water is going to be a major problem. We recently came south from WA, and after entering CA went by Shasta Lake (pretty much the north end of the CA Aquaduct system, from which the central valley farmers get their water, not to mention Los Angeles). My wife grew up in that area, and she has never seen the lake so low. From I-5, areas that are normally under water are high and dry, 50 feet or more above the waterline. If Shasta is that low, it is a pretty good guess that the lower lakes are in the same shape. Unless there is a very very wet winter, and it hasn't been so far, things are gonna get ugly this summer. We have heard that farmers in the valley are going to have to pay as much as $600+ per acre foot, reportedly WELL above what they normally pay. We suspect that more than one farmer is just not gonna plant this year, and those that do plant will be charging super high prices for their product. And you can be sure that high prices will be passed on to the consumer...

As you and Izzy point out 2100 is a few years away.

A lot can happen between then and now.
Peak oil, wars, disease outbreaks, rising oceans, storms... The list of things you can let terrorize you is endless.

I am a bit alarmed by the "Technology will fix it!" attitude of the people trying to debunk it, but I don't think Global warming will be the major cause of reduced food production.

For one thing Peak Oil factors into agriculture much more heavily.

Most of us only think of oil as fuel for home heating or vehicles.
We forget about how much oil goes to produce electricity, how much gets turned into plastics for containers and clothing, how much is turned into chemical fertilizers, and how much is used to plow fields and run factory farm livestock operations, to fish the oceans.
After all that how about the oil used to save and to transport all the food into the cities.
I would bet that the rising cost of refrigeration alone would cost more in lost food than the temp increase would in the near future.All of the oil used to replace agricultural product would need to be replaced by raising even more crops and animals.
Add to this the need for fuel and building materials, and consider that we have already depleted most of the world's forest reserves... again this could be a very long list of effects.
Without a plentiful supply of oil at this time we are already well above the carrying capacity of the planet for humans.

And Peak oil is only one of the factors.

Remember the great Banana scare?
There was a new disease which looked like it might destroy the Cavendish type banana.
All food type bananas are Cavendish and banana is a staple food for many tropical nations, not just desert.
The disease is being controlled by quarantines and inspections because the geneticists have not found a way to make an immune banana yet. It should remind history buffs of the Irish Potato Famine.

I will stop there with the scenarios. It is too easy to become paranoid about it.

I recognize there may be big problems over the distant horizon, and if we continue sailing the course we are on we might sail right over the edge of the Earth!
(how about that for a stretched metaphor)

Unfortunately I have a few things which are more immediate on my priorities list than saving the planet right now.

"I find it a bit ironic that air conditioning is a cause of global warming."

I only "worry" about those things that I can either prevent or mitigate.

My emergency supplies and equipment are for those and to provide options for all of those things that are beyond my control or influence.

Good viewpoint wildman800. Only worry about the stuff you can change!

Exactly right, running out of food 90 years from now occupies about as much of my daily attention span as the next comet collision extinction event does.
You said it so much more simply!

Interesting bit about the banana but the potato "famine" wasn't caused by any natural disaster or disease, unless you count human greed as a disease.

The potato "famine" was caused by sellers of potatoes.

JohnE

No, the potato famine was caused by a fungal blight. The blight is still here in our potato crops. But we control it better and have more resistant types of potato.
http://en.wikipedia.org/wiki/Phytophthora_infestans

The Irish potatoes were all of one type and all descended from one original plant. They had no resistance.

One reason why potatoes fed the Irish was they were cheap food.
They could get 10 times as much food out of a field by growing potatoes instead of wheat or barley.
So the Irish peasants grew potatoes in their own fields and grew grain in their landlords fields for export.

Why the Irish starved so badly while Ireland shipped food to England is another story, and you would be right to blame the severity of the famine on bad politics and greed.

If it wasn't severe it wouldn't have been called a "famine". And it was only a famine because of landowner greed. There was a blight but that's not what caused the problems. It's not another story, it is part and parcel with the blight.

JohnE

Either way, it was a disaster, and I am certainly not arguing that greed played no part.
I agree that greed and stupidity are the two biggest causes of disasters.

What I mean by another story is that it gets into the manor system, business politics, cash crops, subsistence crops, absentee landlords, plantation economies, market distortions caused by foreign trade, the role the English House of Lords played, and all sorts of such stuff.

We could look at modern examples in South America, India, Asia and Africa.

But this forum is not for that type of story, so I won't go there.

I would bet that we would find we mostly agree about what made the Irish problem with failed potato crops so much worse than it should have been, if we were discussing it.