As Decoded Science has pointed out regularly, the claim of climate-change-deniers that global warming stopped in 1998 is totally wrong.
The National Oceanic and Atmospheric Administration’s (NOAA) National Centers for Environmental Information (NCEI) has finally published a definitive study that makes it clear that deliberate or simply misguided misuse of the statistics have only served to obfuscate the obvious.
The notion that global warming leveled off after 1998 was fueled by an unfortunate statement in the Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report, released piecemeal from September, 2013 to November, 2014. Along the way, IPCC concluded that warming during the period from 1998 to 2012 was markedly slower than that during the period from 1951 to 2012.
The scientists of the IPCC are some of the best in the world and they should have known better. In fact, they DID know better. They immediately qualified their “hiatus” announcement by stating that the period of record was short and began with the anomalous El Niño year of 1998. This qualifier makes the previous pronouncement irrelevant, as it is based on arbitrary use of the statistics.
What The NOAA/NCEI Report Says
The NCEI report has the benefit of new data and upgraded re-analyses of old data. There are four major factors in the newly calculated rate of warming:
- Data from marine buoys and ships were re-examined. The trend has been towards more buoy data and less ship data. Because buoy temperatures tend to be cooler than equivalent ship temperatures, the data showed a bias towards cooler temperature over time. The new analysis corrects for the difference between the buoy and ship temperatures.
- Surface coverage has increased over time, as more observation stations are established. The old data were re-analyzed to incorporate what is now known about the temperatures in areas of previously sparse data representation.
- The increases in arctic temperatures, which were underrepresented in the old data due to minimal numbers of reporting stations, have been updated to include new spatial coverage of the temperatures in the Arctic.
- Finally, the last two years of data, including 2014, the warmest year on record, have been added to the data sets.
When all these factors are taken into account, the new temperature record shows that the “hiatus” was imaginary. According to Thomas R. Karl, Director of NCEI:
“Adding in the last two years of global surface temperature data and other improvements in the quality of the observed record provide evidence that contradict the notion of a hiatus in recent global warming trends.” He added, “Our new analysis suggests that ….. the rate of warming over the first 15 years of this century has, in fact, been as fast or faster than that seen over the last half of the 20th century.”
The emphasis is mine, but emphasized or not, there is the possibility that the global increase in temperature, far from taking a hiatus, is actually accelerating.
Are The Data Correct Now?
Statistics are slippery things. As the foolish IPCC claim about a hiatus in global warming shows, even the best and brightest can get an analysis of them wrong.
So do we have it right this time? Since we’re trying to approximate the temperature over the entire earth, we’ll never have it completely right: There are mountains, valleys, ocean currents, and other factors that introduce uncertainties into any use of the data. But the enduring trend from lower left to upper right in any long-term graph of temperature cannot be so wrong as to be subject to any uncertainty that the global temperature is rising.
Furthermore, since there is a perfectly good theory to account for why this is happening, it seems pointless to continue to argue over what is clearly settled science.
Global Warming in a Nutshell
Scientists know that the exhaust from burning fossil fuels contains a large amount of carbon dioxide; carbon dioxide is transparent to solar radiation (in the visible part of the electromagnetic spectrum) and opaque to the earth’s radiation which is in the microwave portion of the spectrum. The inescapable conclusion is that heat will be trapped in the ocean-atmosphere system.
Furthermore, we have a perfectly good example of this “greenhouse effect” at work. The planet Venus, with its CO2-rich atmosphere, is over 800 degrees at the surface.
One More Irrelevant Claim
Those who deny the anthropogenic cause of global warming point out that both the concentration of carbon dioxide in the atmosphere and the temperature have changed by substantial amounts in the past. This is as irrelevant as it is true: The temperature of planet earth has indeed varied from an icebound average of below freezing to a greenhouse-hot reading tens of degrees higher than the present global average. But the changes have never come at such a pace.
Past changes have taken place over time spans of tens of thousands to tens of millions of years.
A rate of change of one and one-half degrees Fahrenheit in the approximately one hundred and fifty years since the start of the industrial revolution is unprecedented outside of rare episodes of violent solar or volcanic activity, or encounters with large extraterrestrial objects (comets or asteroids).
The Warming Is Not In Doubt — But The Future Is
The temperature record shows an unmistakable trend: Up. It is tempting to assign a linear function to this trend. If that is the case, then without action to curtail the greenhouse gas emissions, the earth will be ten degrees hotter in a thousand years. That may not be entirely pleasant, but it will be livable.
But what if the actual function is geometric (increasing by a common ratio of, say, two every hundred years) rather than arithmetic (increasing by a common difference of one degree every hundred years)?
If that’s the case, then eight hundred years from now the temperature at the poles will be over 100 degrees.
The planet will be uninhabitable.
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