by longhorndave
Global warming stopped in 1981… no, wait! 1991!:
[Via Skeptical Science]
The modern global warming trend began around 1975 and has shown a long term warming trend of 0.18°C per decade since. That’s not to say the warming trend has been monotonically constant with each year slightly warmer than the previous. Short term weather fluctuations cause a noisy signal. Large volcanic eruptions lead to dramatic cooling over several years. El Nino/La Nina has a cycle of warming and cooling lasting 4 to 5 years. To demonstrate climate’s variability, let’s examine a 6 year record early in the global warming period.
Figure 1: Land-ocean temperature anomaly (NASA GISS) 1981 to 1987.
[More]
Skeptical Science is great at providing useful scientific debunking of climate denialists’ arguments. In fact, it has one of the web’s single best pages for anyone who wants to discuss the arguments about global climate change. It displays a thermometer recording the top 10 false claims.
In this post, written by John Cook, we get a great explanation of one of the denialists’ favorite tricks – cherry picking data. By only looking at a well chosen sub-set of the data, thay can make any claim they want. Like the world is really cooling.
John leads you through the argument, then reveals the final answer. There have been lagging trends in global warming where the temperatures do not go up very far. As can be seen in the final figure, every time in the last three cycles when solar activity decreases, there has been a pause in global warming. But this pause has been at a higher temperature than the previous cycle.
When this next cycle starts, we will be in for another large temperature increase. The next time it pauses, it will be at a higher plateau then we are now. Unless we reduce carbon emissions this will continue.
Technorati Tags: Environment, General, Sustainability
April 10, 2008 at 1:46 pm
why are carbon emissions your target?
April 10, 2008 at 2:01 pm
Why the delay in posting my question? It’s a fair question.
April 10, 2008 at 3:00 pm
Well, it looks like the server time is a little off because it is only 6:30 AM my time. I’ve got to get some sleep.
What other emissions would you target? Carbon in the form of carbon dioxide and methane are major greenhouse gases that are generated by human efforts, with CO2 being the largest amount generated.
April 12, 2008 at 6:48 pm
CO2 is only a significant greenhouse gas between -18 c and + 15 C . The most important ghg is water vapour. There are nine absorption wavelengths for H2O and three for CO2. Even the UN IPCC states that in the science. In the meantime the unintended consequence is you are burning food for people in your vehicles and planning to sequester plant food. I don’t get the priorities here. The backlash should be swift.
April 12, 2008 at 10:59 pm
You are correct. Water vapor is a more dominant greenhouse gas than CO2. I do not know of anyone who states differently.
Water vapor levels are also very sensitive to temperature and to CO2 levels. Increase in either results in increasing water vapor, producing higher temperatures and more water vapor. It is a positive feedback loop.
Water vapor increases will just about double the warming effects of CO2 alone. So, if enough CO2 was added to the atmosphere to increase the temperature about 1° C, the added positive feedback from water vapor would increase the temperature a total of 2° C
But I am sure you know all of this. I fail to understand why attempting to sequester carbon that was not being used by plants to begin with, that was sitting thousands of feet below the ground, is a bad thing?
The carbon in the Kergen shales is not being used by plants. If we decide to use the hydrocarbons for fuel, how would sequestering that carbon have any effect on plant life?
I would discuss the rest of your comment if you told me what policy you are referring to that results in the ‘unintended consequence’ of ‘burning food for people in your vehicles and planning to sequester plant food?’
April 16, 2008 at 7:14 pm
Burying waste water down the Rocky Mountain arsenal disposal well caused earthquakes in the Denver area in the 60s. It lubricated faults that were in equilibrium and noone even knew they were there, and it had to be stopped. Sequestering CO2 deep underground might have the same unintended consequence anywhere you do it. Let nature take care of the CO2.
April 16, 2008 at 11:47 pm
I don’t have any doubt that Nature will take care of the CO2. I have a concern that Nature’s solution may not be one conducive for 9 billion people.
Our creativity and innovation broke through the Malthusian barrier over the last 200 years. Let’s unleash it to develop something a little more sustainable than the present hydrocarbon-based environment.
I do not think I will change your opinion nor you mine. I have appreciated the discussion and am glad it remained cordial.
Thanks for taking the time to comment.