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Droughts Linked To Global Warming
Layzej writes "Two new papers indicate that we are likely already seeing some of the predicted impacts of global warming. The first used Monte Carlo simulations to analyze how many new record events you expect to see in a time series with a trend. They applied the technique to the unprecedented Russian heat wave of July 2010, which killed 700 people and contributed to soaring wheat prices. According to the analysis, there's an 80 percent chance that climate change was responsible. The authors have described their methods and how they improved on previous studies. The second group studied wintertime droughts in the Mediterranean region. They found that 'the magnitude and frequency of the drying that has occurred is too great to be explained by natural variability alone. This is not encouraging news for a region that already experiences water stress, because it implies natural variability alone is unlikely to return the region's climate to normal.'"
It's called "climate change" NOT "global warming".
It's called both. It is anthropogenic (human-caused) emissions of CO2 causing global warming of mean land, sea, and lower atmosphere temperatures which is causing global climate change.
The unusual weather events we've been seeing around the world the last year aren't proof that global climate change is real... at least not yet. Weather != Climate
That is the opposite of the conclusion reached by these two papers. The papers found that the events in these regions are more likely with the current warming, and would not likely have occurred if it were not for the recent warming.
If ten or twenty years from now the temperature hasn't gone up any more and the weird weather events go away without us taking any action about it i'll be willing to stand up and say i was wrong.
You should expect to see another record year in two or three years (barring a super volcano). Waiting for 10 or 20 years before you reconsider your position is extreme in my opinion. On a somewhat related note, one of the interesting findings of the first paper is that we should expect fewer record years from temperature series that show greater natural variability. For instance, the UAH series exaggerates El Nino/La Nina events relative to other series, so we should expect fewer record years from that series, even though the trend is the same.
According to a survey, 90% of scientists from the relevant fields and 90% of all scientists ascribe to anthropogenic climate change. That is what we call a "scientific consensus", and you don't get a consensus that strong without an awful lot of data to back it up. I know, I know, the good pro-science guys at FOX News and on the Rush Limbaugh show and from the rightist think tanks keep saying this is "bad science", but let's take a look at the "science" the rightists use to make their arguments, shall we?
The most prominent, most cited, and most published climate change skeptic scientist is one Ross McKitrick, who is either an amazingly sloppy scientist, or someone deliberately engaging in fraud in order to promote a purely ideological view. I'll let you read for yourself: http://crookedtimber.org/2004/08/25/mckitrick-mucks-it-up/.
This guy who either literally doesn't know a degree from a radian or is deliberately doing bad science in order to deceive people is the best of the bunch. The others are even worse. It is on the basis of work by men of this caliber that you conclude that 90% of the scientists on the planet, representing people from every conceivable walk of life, economic status, nationality, set of political views, etc. is part of a vast international conspiracy to... what? Make American rightists feel bad? I was never entirely clear on what this vast, incomprehensibly complex conspiracy is actually supposed to do.
The current temperatures are not the perfect ones for the planet. The planet doesn't care. The current temperatures are perfect for us and the food crops and animals we have based our civilization around.
these papers don't prove anything
Proofs are for mathematicians. You can't make a "proof" that we aren't living in some Matrix-style virtual world, where the climate is controlled by The Architect. What scientists can do, however, is to establish the most likely hypothesis to explain some observed data, and provide error bars for acceptance of said hypothesis. And that's pretty important.
Warmer temperatures cause greater evaporation and greater precipitation. Period.... anybody who is predicting more droughts, on average, due to warmer temperatures is -- ahem -- all wet.
Not really, because as you point out changes are regional in scope. That means that it is possible for some regions to get hotter, some colder, some wetter, some drier. If the regions that already have a large rainfall get a lot more rain (enough to significantly increase the global average), and regions that are on the drought boundary get slightly less rain, then the number of droughts will increase, even though the global average rainfall has also increased. I'm not saying that is what will or won't happen, but logically the two outcomes of "greater global rainfall" and "increased drought" are not mutually exclusive.
What I can't understand is how the Earth's temperature has remained essentially static (with a slight downward trend) for the last 12 years.
Because they haven't. Here are all the major temperature reconstructions. All agree that the last 12 years showed warming. http://www.woodfortrees.org/plot/gistemp/offset:-0.074/mean:12/from:1999/plot/hadcrut3vgl/mean:12/from:1999/plot/uah/offset:0.225/mean:12/from:1999/plot/rss/offset:0.14/mean:12/from:1999
Seriously, how can you imagine that there has been a slight downward trend when 2010 was the hottest year on record?
The guy who is primarily responsible for the spread of claims of weather extremes [colorado.edu] has been caught in his lies.
There isn't just "one guy" who says this. There have been hundreds of papers showing links between weather extremes and global warming. To be fair, weather extremes aren't always bad either... if the "extreme" is that a major rainstorm passes over Texas right now, that's better. The problem is that (as was stated above), we've built most of our society around assuming the climate that existed before global warming. If this changes drastically, a lot of people are going to die before we settle back into whatever the new normal is climate-wise. It's not that global warming is bad per se, just that it's bad if it occurs too quickly for humanity and the ecosystem to respond.
Oh, and then there's the fact that increased CO2 is turning the oceans acidic. That gets much less news, but is potentially much more destructive from a world-wide perspective. And there's no possible way you can say that isn't associated with CO2 levels in the atmosphere. And all you have to be able to do to know that's anthropogenic is how to count.
If you increase the concentration of CO2 in a mixture of gases like the atmosphere with infrared radiation passing through it it will warm up by capturing more of that IR. That's simple physics. Human burning of fossil fuels has put more than twice as much CO2 into the atmosphere as it takes to raise the level from 280 ppmv in 1830 to 390 ppmv in 2011. You're going to need some pretty extraordinary evidence to show the increase in CO2 is not the primary cause of global warming and humans are not the primary cause of the increase in CO2. Good luck with that.