I'd like to know how they determined temperature changes in the 19th century in remote seas where no ships traveled.
But, yes, the world is warming. It's been warming since the little Ice Age which ended around 1800. The graphic only proves correlation with rising CO2, not causation.
The world has experienced peaks and troughs in temperature long before we started burning carbon. In the present epoch there seems to be about a thousand year cycle. It so happens that the temperature peaked around 1000 AD as well as 2000 AD. There were also cold spells around 700 AD and around 1500 AD. Until science can explain why these cycles happen, I won't believe carbon burning is the cause of the present warming.
If there were any doubt that a real warming trend is upon us, scientists at NASA have produced a visualization that depicts the recent rise in global temperatures as felt over a span of 130 years.
While the video shows a clear pattern of seasonal temperature changes along with momentary spikes throughout the centuries, you can see that it’s only recently that temperatures in most regions of the world (represented with intensified colors) started to really peak. In fact, since the year 2000, we’ve experienced nine of the 10 warmest years on record. And the researchers have noted that within the past 11 years, temperatures were significantly hotter than in the middle and late 20th century. For instance, the average temperature globally in 2011 was 0.92 degrees F (0.51 C) warmer than baseline temperatures in the mid-20th century.
The warmest years on record were 2005 and 2010, registering as a virtual tie.
“We know the planet is absorbing more energy than it is emitting,” said James E. Hansen, Director of NASA’s Goddard Institute for Space Studies. “So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record.”
Related: Interactive map reveals effects of climate change in your neighborhood
The weather data was culled from more than 1,000 meteorological stations around the world, satellite measurements of sea surface temperature and recordings from an Antarctic research station. Researchers then used a computer program (available to the public) to calculate the difference between the surface temperature in a given month and the average temperature for the same place from 1951 to 1980, which served as a baseline for the analysis. Similar results from the UK’s Met Office Hadley Centre and the National Oceanic and Atmospheric Administration’s (NOAA) National Climatic Data Center corroborated with NASA’s findings.
And if you’re wondering about the link between CO2 and global warming, here’s what the data from NASA shows:
- The carbon dioxide level in the atmosphere was about 285 parts per million in 1880, when the GISS global temperature record begins.
- By 1960, the average concentration had risen to about 315 parts per million.
- Today it exceeds 390 parts per million and continues to rise at an accelerating pace.
While scientists don’t expect temperatures to rise consistently year after year, they do expect those figures to continue climbing over decades with extreme temperatures predicted in the next two to three years due to increased solar activity and the effects of El Nino on the tropical Pacific region.
“It’s always dangerous to make predictions about El Niño, but it’s safe to say we’ll see one in the next three years,” Hansen said. “It won’t take a very strong El Niño to push temperatures above 2010.”
More infographics and interactive maps:
- Infographic: Which American cities are most vulnerable to natural disasters?
- Infographic: What is the water footprint in the U.S.?
- Infographic: Interactive map shows nuclear disaster hotspots
- Infographic: Interactive map shows which neighborhoods are safe?
- Infographic: Where HIV cases are most prevalent
- Infographic: How being a liberal or conservative shapes your life
