IPCC's "Darkest Yet" Climate Report Warns of Food, Water Shortages 703
The Australian reports that "UN scientists are set to deliver their darkest report yet on the impacts of climate change, pointing to a future stalked by floods, drought, conflict and economic damage if carbon emissions go untamed.
A draft of their report, seen by the news organisation AFP, is part of a massive overview by the Intergovernmental Panel on Climate Change, likely to shape policies and climate talks for years to come.
Scientists and government representatives will meet in Yokohama, Japan, from tomorrow to hammer out a 29-page summary. It will be unveiled with the full report on March 31.
'We have a lot clearer picture of impacts and their consequences ... including the implications for security,' said Chris Field of the US’s Carnegie Institution, who headed the probe.
The work comes six months after the first volume in the long-awaited Fifth Assessment Report declared scientists were more certain than ever that humans caused global warming. It predicted global temperatures would rise 0.3C-4.8C this century, adding to roughly 0.7C since the Industrial Revolution. Seas will creep up by 26cm-82cm by 2100. The draft warns costs will spiral with each additional degree, although it is hard to forecast by how much."
The work comes six months after the first volume in the long-awaited Fifth Assessment Report declared scientists were more certain than ever that humans caused global warming. It predicted global temperatures would rise 0.3C-4.8C this century, adding to roughly 0.7C since the Industrial Revolution. Seas will creep up by 26cm-82cm by 2100. The draft warns costs will spiral with each additional degree, although it is hard to forecast by how much."
Re:We've gone beyond bad science (Score:5, Interesting)
At this point, the IPCC is looking more like bad disaster fiction.
What problem do you have with the data?
The problem a lot of people have understanding AGW is separating the science that is settled from the unsettled predictions. There is widespread consensus that CO2 warms the atmosphere, and that anthropogenic CO2 has warmed it to some degree.
At the same time, there is a lot of science that is mere hypothesis. Very few scientists think the runaway Venus effect is realistic, for example.
The approach of the IPCC is to take the worst scenario that hasn't been conclusively rejected by the scientific community, and promoting that scenario most prominently, which is why we you see it being presented with judgement words, like "darkest yet." Their goal seems to be to make it look as dark, which is obviously not a good scientific approach.
Re:We've gone beyond bad science (Score:2, Interesting)
Compare temperatures on Venus from the magellan probe to the 1976 US standard atmosphere. They are exactly 1.176x higher at 1 atmosphere pressure. What is 1.176? It is the square root of the Sun-Venus distance divided by Sun-Earth distance. So temperature is completely explained by distance from the sun?
Recency bias and global warming pause (Score:5, Interesting)
Much of the global warming skepticism has been fueled lately by the decade long pause in the global warming average. It seems what I can gather from this is while many areas are hotter than they were previously, other places are somewhat cooler, so it balances out.
Some of the skepticism does exhibit a recency bias, by simply ignoring everything prior to year 2000 or so. In a chart of temperatures during the past 100 years, the current pause does look rather insignificant and could be simply a temporary pause rather than a change in the trajectory. They have problems explaining away the previous 50 years of temperature increase.
Re:How do food shortages make sense for warmer cli (Score:3, Interesting)
First, we need some references for your claim that in the period when Europe was unusually warm there was increased overall agricultural output there. Maybe, maybe not. Second, Europe is on the whole on the cool side of temperate. It's way north on the globe. The larger proportion of the world's human population and agricultural lands are in warmer climes, many of which are already borderline in terms of water and relief from heat. If more wheat grows in Canada 20 years from now, but the central US is a permanent dust bowl, that's a problem if you're not Canadian. It can also be a problem if you are Canadian, since the US is likely to one way or another annex your land, or else insist you provide us wheat on very favorable terms.
Re:Credibility (Score:5, Interesting)
Please pick up "Six Degrees" and read it.
You are woefully ill-informed if you believe 5C simply "sounds like a lot" but "local variations are far greater". The effects of Climate Change due to Global Warming are not limited to it being just a little warmer. 5C will make things very difficult.
To your point, you need to separate the purported propaganda of us reaching a 5C increase by 2100 vs. the effects of a 5C increase. Yes indeed it is one thing to go on and on about the effects of full scale nuclear war (or a catastrophic asteroid strike, Yellowstone erupting, or whatever) while ignoring the related probability of such an event. But it's foolish to debate the effect rather than said likelihood. These are separate issues/debates. Documenting what has happened in the past at certain temps is probably quite a bit more "settled" than predicting things for the rest of the century.
Re:sugar (Score:4, Interesting)
Re: Well you're partly right (Score:0, Interesting)
You sir are an idiot. You need to get put more and stop watching Faux news so much.
How much snow is on the Sierra Nevada mountains this year? And How the hell Could California screw that up?
Re:sugar (Score:5, Interesting)
because large chunks of land are currently frozen. Canada and Russia(the two largest countries) have tons of land but only a small percentage of those lands are farmable.
I keep reading people saying this, but it doesn't work that way. I can’t speak to Russia, but of the “tons of land” in northern Canada, the vast majority of it is either Laurentian Shield or frozen muskeg.
If the climate over the Laurentian Shield warms enough to grow agriculture crops, we will be able to grow ... as close to nothing as makes no difference. The Shield was scraped bare during the last glacial maximum. The vast majority of the Laurentian Shield has soil only one or two inches deep, below which is the bedrock of the Shield.
If the climate warms enough to thaw the muskeg, we will be able to grow ... as close to nothing as makes no difference. Muskeg is peat bog. It is next to useless for agriculture.
Even worse, when the muskeg thaws it will give off CO2, potentially vast quantities of it, resulting in a potentially huge positive feedback loop, accelerating climate warming.
Re:sugar (Score:4, Interesting)
You assume there will be an even distribution of warming across the globe. And that the shift won't bring unforeseen issues.
It's not just a matter of "everywhere gets X degrees warmer". Not when a substantial amount of water changes its state.
Re:How do food shortages make sense for warmer cli (Score:5, Interesting)
Your error is in assuming a simple, isolated system and ignoring the complexity of dealing with the horribly analog world of biology.
In general, there are two considerations for when, and how much, plants grow. The first is the amount of sunlight they receive (hours per day) and the second is the number of "degree days". Since duration of sunlight isn't going to change (at a certain latitude), let's focus on "degree days" first.
A "degree day" is based on the temperature of the day, so the higher the temperature - the higher the value. However, there are bounds for this. For example, corn needs at least 50 degrees Fahrenheit, but not more than 86 degrees Fahrenheit. i.e. - Below 50 means "0 degree days" and 92 will be the same number of degree days as if it were 86.
The problem comes in when it is far too warm which, for corn, comes in around 86 degrees. The plant hasn't adapted for growing in temperatures much higher, and will shut down growth; much higher temperatures will even cause damage to the plant. Here is a human analogy - a human might be able to run really fast and really far but, if it is 115 degrees outside, that isn't going to happen and any activity may result in heat stroke. A plant will be stressed in this kind of heat and will actually be damaged. In this way, too much heat will cause plants to grow less, and we will have lower yields.
However, since plants also depend on certain amount of sunlight, it isn't a simple matter of moving things northward (or southward in the Southern Hemisphere) to match temperature. All of the plants are also expecting a certain duration of sunlight. This isn't constant with latitude, so moving the plants north will reduce yield. (And more sunlight doesn't mean higher yield - plants also do things at night like release water vapor.) This means that we will have to reengineer our crops to match new conditions - which will take decades. (And crop genetics isn't a simple matter - companies spend billions on trying to make better species.) So, until we do that, we will have lower yields.
Also, many plant diseases like the heat (or like that they don't freeze to death in the winter - see Asian Soybean Rust ranges) - so they will enjoy millions of square miles of new territory - increasing the cost of production (herbicides and pesticides) and, since bugs and molds eat the plants, will give us lower yields.
The other problem is related to economics and infrastructure. Farmers have certain equipment to plant and harvest the crops native to their area. Plus, their fields have been designed for those certain crops. For example, they may be terraced in a certain way or be designed with a certain level of drainage based on existing weather patterns (temperature and rainfall). Renovating millions of square miles of farmland is going to be expensive and ridiculously time consuming and until it is modified to match new, prevailing weather patterns, will contribute to lower yields.
The other side to the economic coin is that decisions are not going to be made on a 50-100 year strategy. To operate next year, a farm needs to turn a profit this year. So, they aren't going to completely retool if yields go down 10% - it would make no sense. The capital costs would dwarf any profit from the new crops being put in. Therefore, they will operate at lower capacity and accept a lower profit - since it is still a profit. Sure, we will get changes when push comes to shove, but that will take decades as climate change forces them to change. Until that point - lower yield.
Moral of the story, we are looking at decades of lower yields as climate change really kicks in.
Re:We've gone beyond bad science (Score:5, Interesting)
Also note the IPCC doesn't do any research, rather they "[assess] the scientific, technical and socio-economic information relevant for the understanding of the risk of human-induced climate change."