Climate change deniers like to take graphs of surface air temperatures for the last 10 years and claim that they disprove that the earth is warming. This is “cherry-picking” the data.
Look at the following graph from NASA. If you only focus on the past 10 years, you might think that things have stabilized. True, the graph has several dips, but the overall trend is upward. In 1970 you might have thought that things were stable, but in retrospect it was only a long pause. It’s like having a cool week in May and saying that the “Summer is Coming” theory is wrong.
Another problem is that this graph only shows surface air temperatures. There is a lot more to the earth than the surface air. The following graph shows ocean water heat content, which has continued to rise in the past decade. You could dishonestly show a graph starting with the outlier in 2004 and say it shows that ocean temperatures are stable, but any scientist can tell you that outliers happen. Events such as El Nino and volcano eruptions can have significant short term effects on the climate. Disregard the one high point in 2004 and the one low point in 2001 and the trend is obvious and undeniable.
And this graph shows historic arctic ice coverage, with the sudden decrease in the past century.
Here’s a graph of recent ice coverage. Note that there used to be a lot more sea ice in the arctic than antarctic. Arctic summer ice coverage in 2013 was barely half of what it was in 1998, when deniers like to say that warming stopped. Antarctic sea ice coverage has been pretty stable over the decade, and it’s not fully understood why. But the loss of total world sea ice coverage is clear.
And noting that the ice is not just decreasing in coverage, but also in thickness, here’s a graph of arctic ice volume. The jiggly up and down reflects the seasonal variation. Rather than stabilize, the rate of decrease seems to have accelerated in the past decade.
A little physics: When you have a mixture of ice and water, the temperature is going to be stable at 32 degrees Fahrenheit. As you add heat, the temperature will not change, but the ice will continue to melt into water. Only after all the ice has melted will the temperature of the mixture begin to rise. The point is that for ice to melt heat has to go in. The heat content of the system continues to increase though the temperature stays the same.
The melting of the ice caps and glaciers around the world along with ocean warming shows that total heat in the earth has continued to increase over the past decade, despite the pause in surface air temperature.
There is a strong vested interest by many corporations and industries to deny global climate change. The acceptance would lead to policies that would decrease their profits. Huge amounts of money go into climate change denial, and it’s become a popular Tea Party position. A lot of the strategy is taken right out of the 1990s Tobacco industry playbook to deny any health impact from smoking; e.g. cherry-pick the data, find the 1 or 2% in the field who disagree and push them as the real experts, and lobby lawmakers. For example, a memo was leaked from the American Petroleum Institute about a plan to “recruit a cadre of scientists … and to train them in public relations so they can help convince journalists, politicians and the public that the risk of global warming is too uncertain to justify controls on greenhouse gases.” They offered scientists $10,000, plus travel expenses to publish articles critical of climate change. Statements were taken out of context from scientists’ emails and published to imply that climate scientists were colluding to fool the public (“Climategate“). Wikipedia lists several other examples of industry and far right groups donating millions of dollars in efforts to discredit the science and influence politicians and public opinion. An example of the results of their efforts are the trumpeting of any piece of data that seems to discredit the theory, such as the recent 10-year surface temperature graph, rather than viewing the data as a whole.
Climatology is not a simple science. I trust the roughly 98% of climatologists who agree that the climate is changing more than television pundits, bloggers and columnists who know nothing more about climate than what they feel when they go outdoors, and who want to keep their corporate sponsors happy. It has nothing to do with “Left” vs. “Right”, it is about science vs. politics, reason vs. profit.
