“NOAA: June, April to June, and Year-to-Date Global Temperatures are Warmest on Record”
The following figure from NOAA shows the temperature anomaly of January – June 2010 compared to the 1971-2000 base period for 5×5 degree grids [http://www.noaanews.noaa.gov/stories2010/20100715_globalstats.html]
The problem with the above map: data quality and data manipulation.
The following sections provide some spot checks on the areas of the world exhibiting the most warming according to NOAA. The gridded historical data graphs shown in these sections are from the Hadley CRUTEM3 database for January – June. (CRUTEM3 uses a 1961-1990 base period whereas the NOAA data above is for a 1971-2000 base period. This simply shifts the anomalies on the vertical scale, but does not affect the relative trends.)
It is clear from the following sections that NOAA performs manipulations to create false impressions from the data, including assigning temperature increases were there is zero data.
Spot Check – Northern Africa
It is apparently much hotter than usual in the Sahara. But where is the data? Several of the 5×5 degree grids have zero stations (indicated by the black arrows). Many of the others have one station with very limited historical data. There seems to be an inverse correlation between the number of stations and warming – more stations in a 5×5 degree grid and less warming is observed.
The map figure above shows the location of stations in the NOAA GHCN database (blue G or green B icons) and the red 5×5 icon indicates whether data exists in the Hadley CRUTEM3 database – a 5×5 degree gridded database used by IPCC (plotted at http://www.appinsys.com/GlobalWarming/climate.aspx). The grid lines are 5×5 degree grids.
In many of the 5×5 degree grids showing 4 degrees warming according to the NOAA map, there are only one or two stations. The figure below shows some of the “hot-spots” in the NOAA map displaying January – June average temperature anomaly from the Hadley CRUTEM3 database for 1900 – 2009. In no cases is the warming close to what NOAA indicates.
There is a severe problem with lack of historical data in Africa as well as lack of coverage and gaps in the data. NOAA’s algorithms spread the low quality data across areas that have no data as well as showing warming that isn’t really there.
One must really question the NOAA data when even the areas with many stations seem misrepresented. The following figure shows the area of eastern Turkey which has many stations and shows no warming in Jan-Jun through 2009, but suddenly according to NOAA has 4 degrees in 2010.
Spot Check – Greenland
It is apparently much hotter than usual in Greenland. But where is the data? Most of the 5×5 degree grids have zero stations (only some of which are indicated by the black arrows). Most of the grids with data have one station. The two hottest spots on the NOAA Greenland area show 5 degrees warming and have no data.
Some of the Greenland stations have long-term data. The figure below shows some of the “hot-spots” (that actually have data) in the NOAA map displaying January – June average temperature anomaly from the Hadley CRUTEM3 database for 1900 – 2009.
Spot Check – Canada
It is apparently much hotter than usual in Greenland. But where is the data? Most of the 5×5 degree grids have zero stations (only some of which are indicated by the black arrows). Most of the grids with data
Many parts of the world do not have data for the first half of the 20th century. Without this historical context it is easy to create misleading impressions.
Northern Africa: A lack of historical context. The warming of 1 – 2 degrees since the base period is without historical perspective. This lack of history gives the false impression that the warming is significant.
Greenland: The historical context shows that warming and cooling by several degrees is not without precedent. Recent warming is less than the 1930s. The statement of warming since the 1980s gives the false impression that this is unprecedented.
Canada: Many stations in northern Canada are no longer maintained in the GHCN or CRUTEM3 databases. Warming has been 4 degrees over the last 40 years according to NOAA. The historical context shows similar warming in the 1930s (graph shown previously).
Recent warming in Canada correlates to the El Nino Southern Oscillation (ENSO). The following figure compares the Jan-June temperature graph shown previously for northern Canada with the multivariate ENSO index (from http://www.esrl.noaa.gov/psd/people/klaus.wolter/MEI/).