There is no question that the world has been warming since the mid-20th century and human influence likely is the dominant cause, the Intergovernmental Panel on Climate Change said Friday in the first phase of its 2013-14 report.
The first phase summarizes the scientific data from around the world that will go into the report, the panel's fifth since it was set up in in 1988 by the United Nations Environment Program and the World Meteorological Organization.
Among other points, the summary said each of the last three decades has been warmer at the Earth' surface than any previous decade since 1850. The average extent of Arctic sea ice has been shrinking each summer and each succeeding decade since 1979, it said.
An article about the first phase attracted a lot of comment from syracuse.com readers. Here's a sample:
From marat: I am surprised people actually think billions of humans do not have an influence on climate. The problem with ferreting out the real facts comes, as usual, through political interference from both extremes . . . the loony left tries to suppress and data not meeting their agenda, while the corporately funded radical right has its own reams of junk science to confuse the picture.
We are clearly despoiling our own nest. Beyond that, very little is clear and the fog banks are definitely man made.
From jlkinsella: The first figure above shows two periods of warming since the end of the "Little Ice Age" about 150 years ago. Interestingly, they both (1910 to 1940 and 1970 to 2000) are very similar in the rate and in the amount of warming. Yet, our friends at the IPCC have different explanations. Tell me if their "explanation" makes any sense.
Thy conclude that the earlier warming is caused natural causes that are not known, but don't involve CO2 because it didn't change much. The more recent warming was not caused by the undescribed natural causes of the earlier period, but were caused by raising CO2. No reason given why two different explanations are used for essentially the same observations other than computer modeling told them so. (Unfortunately for the IPCC the models failed miserable to account for the now 15-plus years of no warming. So much for computer weather modeling of climate.)
The second figure are computer models of future temperatures. Why would anyone use models that have already proved worthless in predicting climate? Time to return to doing actual science.
From joe4point0: How to explain the fact that since 1998 the earth's temperature has barely risen? The IPCC, according to an AP investigation, was pressured by governments, including our own, to take out any mention of a hiatus or pause in warming. In a leaked draft, dating from June, the IPCC said that the rate of warming between 1998 and 2012 was about half the average rate since 1951. Germany called for the reference to the slowdown to be deleted, while the U.S. urged scientists to include as its "leading hypothesis" that the reduction in warming is linked to more heat being transferred to the deep ocean. It's interesting how invested certain politicians are in climate change needing to be anthropogenic. It's almost as if there's some political gain to be had by telling people that we need a raft-load of new laws, new bans, new taxes, new programs, etc.
From rhbcazny: I have had to turn on my furnace five times in September. And as far as the IPCC saying the sea levels will rise 10 inches in the next century, take two steps back!
From thesnacker: Everybody posting on this story has done much more research on this subject matter than the scientists who have spent their whole lives coming to this conclusion.
What evidence would conclusively demonstrate a tie between human activity and climate change? Please leave a comment below.