Posted: 27/06/2015 at 13:11
So it seems I need to repeat an explanation of something here.
"Global warming" doesn't mean "exactly the same weather every year just 0.05C hotter each year." It doesn't. Really. St George's Day this year is not predicted to be exactly like St George's Day last year but 0.05C warmer and exactly like St George's Day the year before but 0.1C warmer and St George's Day next year is not predicted to be exactly like St George's Day this year but 0.05C warmer.
There are cycles. There are many cycles, with various lengths. Some are "2- to 5- but typically 3-year" cycles, some are "about 7 year" cycles, some are "10- to 11-year" cycles and so on. Back around 1970, a scientist studying these cycles identified many of them and found a rather curious discrepancy: the 1950-1970 trend was pretty much flat, when it should have been downward. Having given the matter some thought, he concluded that the most likely explanation for this was anthropogenic carbon dioxide in the upper atmosphere since the industrial revolution having a warming effect. At the end of his research paper (yes, I have read it) he said that we didn't have enough information to know what effect continuing CO2 emmissions would have, that based on the scant info available at the time it could make the world hotter and hotter exponentially or steadily, make the world a bit warmer and then stabilise or even trigger a worse mini-ice-age, and that further study would be required before we could be sure what we were doing to ourselves. Ever since then, people have been saying: "Back in the 1970s scientists thought CO2 would cause another ice age!"
Let's get something cleared up here. The prediction is of an upward trend in global annual average temperatures. See the black line on the graph above? TREND. It's not a year-on-year increase. It's an upward trend. If I posted a graph of the amount of money in my current account, day by day, it wouldn't be a smooth line. It would have big jumps where I get paid and big drops where my credit card bills get paid. If you were to draw lines across the monthly highs or across the monthly lows (how much I actually have available for new plants) or across the monthly averages, you would see the trend. Maybe I buy some new hiking gear or pay for a holiday, and there's a drop, but over 5 years you'd see an upward trend. Taking the point after I'd just been paid the month before I got new hiking boots and broke them in and the point after I'd just paid off the credit card bills that included those boots and that holiday, drawing a line across them and saying there's a downward trend and I'm about to go broke would be bullshit. Going from that low to after the next time I got paid and predicting I'd be a millionaire in 2 years would also be bullshit.
Now let's look at "global." That's the world, not 22 Acacia Avenue, Strengville, North Carolina. It's the whole world, all of North America, all of South America, all of Central America, all the Caribbean islands, all of Scandinavia and Europe and Africa and the Middle East and the Antipodes and the Orient and Indochina and the Arabian Peninsula and the Caicos and Galapagos and South Sea islands and Antarctica all the water too. It's a very big place. It's also quite a complicated shape. If you put a small saucepan of water on the stove, the temperature in the saucepan goes up or down pretty evenly with the heat under it. If you put a huge steel bathtub with all sorts of interesting rocks in it as well as a lot of water onto the stove, though, you'll get currents through the rocks and those currents will change with the temperature. The Earth is way more complicated than a bathtub full of rocks and water. We've got reflectivity, clouds, glaciers, deep ocean currents and all that. Different parts can be affected in diffe