Either way, the theory is that there would be more harm in the future from the extra warming of many degrees Celsius, which itself is distributed disproportionately towards colder areas, times of day, and months.
If we said something like "Hurricane Katrina and Typhoon Nargis occurred because of global warming," you would dispute that, because such events could have occurred with or without AGW. That is the problem: no single event has a label on it that says "this one is due to global warming." One could even argue that hurricanes may have been prevented by AGW, and it would be difficult to dispute that also, because hurricanes are rare events and we simply don't have the statistics on it.
That is why your comment to Alph, to "Be more specific" just sounds hollow and self-serving, you realize that you're asking for something that at the present time is difficult to impossible. That does not mean the effect is not there, though. I used to work on experiments that might have to be run thousands of times before the signal was large enough that it could be distinguished from the noise--but the signal was there all along. However, if you'd asked me to "Show you the evidence" in any particular run of the experiment, I could not have done it--nobody believes a signal that ten times smaller than the noise. I would have told you to wait until I've done 10,000 runs, then the signal would be obvious. It's similar with AGW, except that not only will we have more statistics as the decades grow by, the signal will also be growing larger.
The question that people need to ask is whether it's worth waiting X number of years until the effects of AGW are glaringly obvious, or try to take action while what is seen is more subtle. In most endeavors, it's almost always easier and cheaper to address a problem while it's still manageable and less costly to fix. AGW is no exception. It may be that if we wait long enough, the problem will take care of us, rather than us taking care of it.
As an aside, I see that you have not chosen to address your incorrect statements made recently about hurricanes.
I've got one for ya.
Warming's effect on crops.
http://iopscience.iop.org/1748-9326/2/1/...
The study (if this is the one I'm thinking of) compared yields from adjacent years, and warmer years had lower yields for several of the crops they studied. They studied the 6 largest crops in the world. They compared adjacent years to help control for things like technological gains, atmospheric CO2, new crop varieties, and so on, on the assumption that adjacent years would have similar technology, CO2, et cetera.
Now, crop yields can be affected by a lot of other things (kind of like how climate is affected by things other than CO2). But the CO2 fertilization effect on plants is likely to have diminishing returns, while the effect of warming is likely to increase.
edit:
it does appear to be the one I was thinking of.
Higher temperatures had a negative effect on wheat, maize, soy, barley, and sorghum, though the effects on sorghum were kind of weak. Rice was the only major crop that really wasn't negatively affected by higher temperatures.
Thus spoke Harry S. Truman in the sping of 1980.
The danger from Mount St, Helens was "overexaggerated".
"This area is heavily timbered, Spirit Lake is in between me and the mountain, and the mountain is a mile away, the mountain aint gonna hurt me...boy"
Harry was a good'ol boy Denier. Stupid as dirt....but a good Denier. Just hours before the
eruption - after most of the sane Deniers had accepted reality and fled - Harry kept on Denying.
And being only a mile away, he didn't even have time to enjoy the view - before the pyroclastic flow buried poor Harry under a 150 feet of volcanic debris.
http://www.princeton.edu/~achaney/tmve/w...
One place to start a discussion would be to follow the skepticalscience link on the benefits and harms of AGW.
http://www.skepticalscience.com/global-w...
Howeve, I suspect that a lot of what you would read is more about what could be expected, rather than what has actually happened.
I agree that to say that AGW causes extreme weather is too vague. AGW can aggravate the effects of heat waves and droughts. Warming may actually suppress hurricanes by causing more atmospheric wind shear. But if it doesn't cause more hurricanes, then we don't get the cooling effect that more hurricanes would cause.
If there is negative feedback, we could expect overshoot.
http://en.wikipedia.org/wiki/Overshoot_(...
Apparently Alph's argument is that warming has caused an opportunity to actually use the Arctic and therefore Canada has had to spend millions fending off Russian aggression. I guess with that kind of logic he would think it advantageous if we had a mile high glacier over most of Canada like we did 20 thousand years ago.
The reason they try to use Polar Bears as their poster child is because there are so few examples that might show overall harm in warming beyond their occasional ridiculous examples of runaway warming.
for one, Canada now has to spend millions to assert its arctic sovereignty as the arctic ice melts and shipping/resource extraction becomes more possible..
we're also loading the dice for extreme weather. You cannot change the climate without changing weather.
The change in Ocean pH is already having an effect on some organisms, the start of the long food chain.
It's a lot easier to deny there is a problem.
We now have 14% more plant biomass, plus better crop yields, it's a pity the temperature hasn't gone up a more.
If it wasn't for the Planet's ability to regulate its own temperature, then it would be much warmer. Temperatures are still well within natural climate variability.
If you place those graphs on a table outside and climb a ladder to the roof, then you probably couldn't read the graphs.
My 2nd point is to illustrate how alarmunists can make things look more tragic by showing a lower gradient (i.e. showing 0.5 instead of 1 will show a more extreme graph).
There is no evidence . Weather does not count because nobody linked it on the atomic level .
I'll start by throwing up a graph: http://blogs.agu.org/wildwildscience/files/2009/04/rbrwug0062_model_forcing_100years-733x1024.jpg
This graph shows what the Earth surface temperature would have been if there had been no human influence. Putting aside any arguments regarding whether that in itself is accurate, let me ask a very simple question.
What data or evidence or analysis has there been to show the net harm or benefit of that difference?
There has been no scientifically observable benefit or harm done to the earth. The earth has been hotter and the earth has been colder.
The rise in CO2 would be beneficial to the plants. But the 'saviors' won't sign on to that even though it is more reasonable than the temperature damaging the earth.
The fraud and harm they have done to hard working people , the people at the AGW should be tried and shot for their crimes.
