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better to know...?, climate-debate

Climate Science Double-Speak

by K. Hansen, 2017 in WUWT

A quick note for the amusement of the bored but curious.

While in search of something else, I ran across this enlightening page from the folks at UCAR/NCAR [The University Corporation for Atmospheric Research/The National Center for Atmospheric Research — see pdf here for more information]:

“What is the average global temperature now?”

We are first reminded that “Climate scientists prefer to combine short-term weather records into long-term periods (typically 30 years) when they analyze climate, including global averages.”  As we know,  these 30-year periods are referred to as “base periods” and different climate groups producing data sets and graphics of Global Average Temperatures often use differing base periods, something that has to be carefully watched for when comparing results between groups.

Then things get more interesting, in that we get an actual number for Global Average Surface Temperature:

“Today’s global temperature is typically measured by how it compares to one of these past long-term periods. For example, the average annual temperature for the globe between 1951 and 1980 was around 57.2 degrees Fahrenheit (14 degrees Celsius). In 2015, the hottest year on record, the temperature was about 1.8 degrees F (1 degree C) warmer than the 1951–1980 base period.”

Quick minds see immediately that 1.8°F warmer than 57.2°F is actually 59°F [or 15° C]  which they simply could have said.

UCAR/NCAR goes on to “clarify”:

“Since there is no universally accepted definition for Earth’s average temperature, several different groups around the world use slightly different methods for tracking the global average over time, including:

NASA Goddard Institute for Space Studies

    NOAA National Climatic Data Center

    UK Met Office Hadley Centre”

We are told, in plain language, that there is no accepted definition for Earth’s average temperature, but assured that it is scientifically tracked by the several groups listed.

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climate-debate

Junk Science Alert: Met Office Set to Ditch Actual Temperature Data in Favour of Model Predictions

by C. Morrison, Dec 24, 2023 in WUWT

The alternative climate reality that the U.K. Met Office seeks to occupy has moved a step nearer with news that a group of its top scientists has proposed adopting a radical new method of calculating climate change. The scientific method of calculating temperature trends over at least 30 years should be ditched, and replaced with 10 years of actual data merged with model projections for the next decade. The Met Office undoubtedly hopes that it can point to the passing of the 1.5°C ‘guard-rail’ in short order. This is junk science-on-stilts, and is undoubtedly driven by the desire to push the Net Zero collectivist agenda.

In a paper led by Professor Richard Betts, the Head of Climate Impacts at the Met Office, it is noted that the target of 1.5°C warming from pre-industrial levels is written into the 2016 Paris climate agreement and breaching it “will trigger questions on what needs to be done to meet the agreement’s goal”. Under current science-based understandings, the breaching of 1.5°C during anomalous warm spells of a month or two, as happened in 2016, 2017, 2019, 2020 and 2023, does not count. Even going above 1.5°C for a year in the next five years would not count. A new trend indicator is obviously needed. The Met Office proposes adding just 10 years’ past data to forecasts from a climate model programmed to produce temperature rises of up to 3.2°C during the next 80 years. By declaring an average 20-year temperature based around the current year, this ‘blend’ will provide ”an instantaneous indicator of current warming”.

It will do no such thing. In the supplementary notes to the paper, the authors disclose that they have used a computer model ‘pathway’, RCP4.5, that allows for a possible rise in temperatures of up to 3.2°C within 80 years. Given that global warming has barely risen by much more than 0.2°C over the last 25 years, this is a ludicrous stretch of the imagination. Declaring the threshold of 1.5°C, a political target set for politicians, has been passed based on these figures and using this highly politicised method would indicate that reality is rapidly departing from the Met Office station.

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