One of the problems in assessing global climate is that the surface temperature record is terrible. There are very few weather stations world-wide, and fewer all the time. Seventy per cent of the world is ocean, and therefore hard or impossible to measure accurately. Most temperatures that go into calculations of a global average are not even measured: they are interpolated, assumed temperatures based on records at other stations.
Even when measured, temperature records are not very reliable. The U.S. is generally considered to have the best records, but surveys show that over half of our weather stations do not comply with written standards. Some are located in places that obviously will be warmer than surrounding air, e.g., next to airport runways. Many are in cities, where temperatures are artificially inflated by concentrations of people, motor vehicles, buildings, etc. And on top of all of that, the alarmists who curate weather records have systematically fiddled with them, lowering temperatures that were recorded decades ago and raising recent ones, to exaggerate the supposed phenomenon of global warming.
In order to address some of these problems, the National Oceanic and Atmospheric Administration (NOAA) implemented, beginning in 2005, a new surface temperature measurement system in the U.S.
[The U.S. Climate Reference Network] includes 114 pristinely maintained temperature stations spaced relatively uniformly across the lower 48 states. NOAA selected locations that were far away from urban and land-development impacts that might artificially taint temperature readings.
Prior to the USCRN going online, alarmists and skeptics sparred over the accuracy of reported temperature data. With most preexisting temperature stations located in or near urban settings that are subject to false temperature signals and create their own microclimates that change over time, government officials performed many often-controversial adjustments to the raw temperature data. Skeptics of an asserted climate crisis pointed out that most of the reported warming in the United States was non-existent in the raw temperature data, but was added to the record by government officials.
The USCRN has eliminated the need to rely on, and adjust the data from, outdated temperature stations.
So–not to keep you in suspense–what does the USCRN show so far? No warming:
At Real Clear Energy, James Taylor adds:
There is also good reason to believe U.S. temperatures have not warmed at all since the 1930s. Raw temperature readings at the preexisting stations indicate temperatures are the same now as 80 years ago. All of the asserted U.S. warming since 1930 is the product of the controversial adjustments made to the raw data. Skeptics point out that as the American population has grown, so has the artificial warming signal generated by growing cities, more asphalt, more automobiles, and more machinery.
If anything, the raw temperature readings should be adjusted downward today relative to past temperatures (or past temperatures adjusted upward in comparison to present temperatures) rather than the other way around. If raw temperature readings are the same today as they were 80 years ago, when there were fewer artificial factors spuriously raising temperature readings, then U.S. temperatures today may actually be cooler than they were in the early 20th century.
More at the link. USCRN promises to be a valuable contribution to the raging debate over climate, as long as the alarmists don’t get their hands on the data and start changing it.