The summary quickly showed up everywhere in the news, even at my favorite Ars. Reading through the document does make you think about the future of our climate. 11 of the last 12 years rank among the 12 warmest years ever measured since they started in 1850. For me personally, it has been some great warm and long summers and not a negative thing. For people living in northern Europe like I do, global warming will mostly make things better. The forests and crops will grow better, warmer summers, less freezing winters. The only downside for us will be an increase in precipitation. Most places will not be this lucky.
Although the temperature will increase the most at the poles, it's the places that are already dry and hot that will get the most serious problems. Serious droughts will follow, an increase in wild fires and agriculture and livestock will suffer. That might eventually lead to malnutrition and on top of that, clean drinking water will become a problem. The number of cyclones and storms is likely to increase too, and in low coastal regions and river deltas, increased risk of flooding.
Global increase in temperature for 2099 compared to 1999
The study also expects that in the long term, if the warming continues, the ice caps on Greenland will melt completely and raise the sea level with about 7 meters. This will take some thousand years or so, but it will be a noticeable increase just in the next 100 years.
The primal cause for the emission of green house gases (GHG) is the use of fossil fuels. The concentration of carbon dioxide and methane in the atmosphere is exceeding by far the natural range seen in the last 650,000 years. We need to cut down on the green house gas emissions on a global scale right now, and even using the most optimistic scenarios still points to an increase in global temperature.
A global increase of 1.5-2.5 degrees Centigrade would endanger 20-30% of the species assessed of global extinction. Most scenarios in the summary suggests a much higher increase in temperature...
If all future investments in infrastructure and energy plants are shifted to get the lowest possible CO2 emissions, the additional investment costs would be around 5-10% higher. That's not much at all, and simply increasing efficiency of energy supply and industrial processes would do a lot to stabilize GHG emissions on a global scale. It's good to see that UK is helping China to get started on this.
Maybe we have no choice in lowering our oil consumption. A recent article in Wired states that most likely we will be unable to maintain the current consumption because we just can't pump the oil up fast enough. Some says 10 years more is all we have.
My personal opinion is that oil based fuels are way too cheap. If prices were at least doubled, maybe driving around in a petrol car won't be the cheapest way to travel medium distances any more. Electric or hydrogen fuel cell cars, although still very expensive, would become a more viable option. Flying is also cheaper than it should be, and even though it's nice to be able to afford to fly away for vacation, I wish there was a less polluting option for long trips. I really do.