Het blijft maar rommelen rondom de betrouwbaarheid van de temperatuurmetingen. Klimaatsceptici richten hun pijlen vooral op de zogenoemde ‘homogenisering’ van ruwe temperatuurdata. Door de daaruit voortvloeiende ‘correcties’ wordt de stijging van de gemiddelde wereldtemperatuur versterkt. Sommige sceptici gaan zelfs zo ver om (nagenoeg) de hele temperatuurtoename van de afgelopen eeuw aan deze aanpassingen toe te schrijven.

Onder de titel, ‘Exclusive: Study Finds Temperature Adjustments Account For ‘Nearly All Of The Warming’ In Climate Data’, schreef Michael Bastasch voor de ‘Daily Caller’:

A new study found adjustments made to global surface temperature readings by scientists in recent years “are totally inconsistent with published and credible U.S. and other temperature data.”

“Thus, it is impossible to conclude from the three published [global average surface temperature (GAST)] data sets that recent years have been the warmest ever – despite current claims of record setting warming,” according to a study published June 27 by two scientists and a veteran statistician.

The peer-reviewed study tried to validate current surface temperature datasets managed by NASA, NOAA and the UK’s Met Office, all of which make adjustments to raw thermometer readings. Skeptics of man-made global warming have criticized the adjustments.

Climate scientists often apply adjustments to surface temperature thermometers to account for “biases” in the data. The new study doesn’t question the adjustments themselves but notes nearly all of them increase the warming trend.

Basically, “cyclical pattern in the earlier reported data has very nearly been ‘adjusted’ out” of temperature readings taken from weather stations, buoys, ships and other sources.

In fact, almost all the surface temperature warming adjustments cool past temperatures and warm more current records, increasing the warming trend, according to the study’s authors.

“Nearly all of the warming they are now showing are in the adjustments,” Meteorologist Joe D’Aleo, a study co-author, told The Daily Caller News Foundation in an interview. “Each dataset pushed down the 1940s warming and pushed up the current warming.”

“You would think that when you make adjustments you’d sometimes get warming and sometimes get cooling. That’s almost never happened,” said D’Aleo, who co-authored the study with statistician James Wallace and Cato Institute climate scientist Craig Idso.

Their study found measurements “nearly always exhibited a steeper warming linear trend over its entire history,” which was “nearly always accomplished by systematically removing the previously existing cyclical temperature pattern.”

“The conclusive findings of this research are that the three [global average surface temperature] data sets are not a valid representation of reality,” the study found. “In fact, the magnitude of their historical data adjustments, that removed their cyclical temperature patterns, are totally inconsistent with published and credible U.S. and other temperature data.”

Lees verder hier.

Aangenomen mag worden dat het rode team waarover ik eerder rapporteerde, hier ook naar zal kijken.

Voor degenen die wat dieper in deze materie willen duiken, kan de website ‘ Klimaatgek’ van Rob de Vos worden aanbevolen, die daarover de laatste tijd verschillende interessante ‘postings’ heeft gepubliceerd.

Voor mijn eerdere bijdragen over klimaat en aanverwante zaken zie hierhier, hier, hier en hier.