New study: Global warming ‘Pause’ may not have ended after all
The so-called hiatus in global annual average temperature between 2002 – 2014, once controversial to some but now well-established in the peer-reviewed literature, ended in 2014 with the start of a series of record-breaking El Nino events that spiked global temperature with a subsequent fall-back.
Now a new study into the effect of man-made aerosol pollution adds to likely reasons for the end of the hiatus, and may point to lower estimates for future global warming.
An international research team writing in the journal Atmospheric Chemistry and Physics, uses satellite data to show that concentrations of aerosol particles have decreased significantly since 2000. This is good news as cleaner air benefits health, but it also reduces particles which have a cooling effect on the terrestrial climate.
According to the IPCC, by 2019 the global temperature had risen by 1.1 degrees Celsius compared to pre-industrial levels due to increasing ‘greenhouse gasses’ from burning ‘fossil fuels’.
At the same time the combustion of ‘fossil fuels’ emit aerosols which cool our climate by reflecting sunlight and increasing the reflectivity of clouds.
Professor Johannes Quaas, a meteorologist at Leipzig University, and colleagues from Europe, China, and the US have published robust observational evidence of significant reduction of aerosol pollution and improved global air quality.
“We analysed data from NASA’s Terra and Aqua satellites. They have been providing comprehensive satellite observations of the Earth since the year 2000, measuring incoming and outgoing radiation, but also clouds and aerosol pollution.
The latter has decreased significantly across North America, Europe and East Asia since 2000,” Professor Quaas said.
The researchers estimate that the weakening of aerosol-induced temperature change between 2000 – 2019 is similar to that estimated by the IPCC’s AR6. Most of this weakening occurred post-2010 coincident with the end of the end of the so-called global warming hiatus period.
It suggests that perhaps up to 60 percent of the global temperature increase since then is down to the reduction of global aerosols.
When taken together with a couple of super-strong El Nino events which temporarily drove up global temperature (see graph below), the new findings suggest that the global warming hiatus — clearly evident prior to 2014 — may not have ended yet.
If NASA’s satellite data are confirmed, it would suggest that much of the very moderate changes in global temperature this century may have been driven primarily by cleaner air and naturally-occurring El Ninos.
Global temperature changes 2000-2022. Source: Met Office/HadCRUT5
The new observational data has strong implications for predictions of future global warming, suggesting it might be significantly lower than most models suggest.
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Tom Anderson
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This overlooks one thing, CO2 cools. Arrhenius and Callendar are out of date.
Carbon dioxide is among the several gases that radiate solar energy and the Earth’s outgoing energy away to space. Energy radiated away top-of-atmosphere-to-surface appears in satellite images. It is the deep wedge at 15μm wavelength missing from the outgoing energy curve.
Recent experiment (Wittteman, 2020) shows 99.83% of tropospheric CO2 interacting at the solar 15-micron wavelength. Temperature there, by Wien’s130-year-old “Displacement Law,” and confirmed by observation, is – 80 Celsius below zero. (80°C, -112°F). Other recent research puts CO2 radiation in frigid territory. Chemke and Kaspi (2017) reckoned that Venus’s stratosphere would be at least 44K hotter if it had a N2-O2-dominated atmosphere and much lower O2 concentrations like Earth.
CO2 cannot change atmospheric temperature in any case. Causes must always precede effects, and CO2 levels in the atmosphere follow temperature change on all time scales. Half a dozen recent studies, including one intended as disproof, confirm the lag described in Humlum & al’s original 2013 research. CO2 levels are an effect, not cause, of temperature change.
The foregoing is not anomalous. All have been confirmed by replication.
Remember also, CO2 is about 400 parts per million by volume of our atmosphere. That is 0.04% of the atmosphere. Human-generated CO2 by IPCC estimate is about 5% of that. In money terms, 0.04% of $1,000 is 40ȼ, with people’s share 2ȼ.
Reply
Tom Anderson
| #
“N2-O2 atmosphere with lower CO2 levels”
Reply
Tom Anderson
| #
This overlooks one thing, CO2 cools. Arrhenius and Callendar are completely out of date.
Carbon dioxide is among the several gases that radiate solar energy and the Earth’s outgoing energy away to space. Energy radiated away top-of-atmosphere-to-surface appears in satellite images. It is the deep wedge at 15μm wavelength missing from the outgoing energy curve.
Recent experiment (Wittteman, 2020) shows 99.83% of tropospheric CO2 interacting at the solar 15-micron wavelength. Temperature there, by Wien’s130-year-old “Displacement Law,” and confirmed by observation, is 80 Celsius degreesbelow zero. (-80°C, -112°F). Other recent research puts CO2 radiation in frigid territory. Chemke and Kaspi (2017) reckoned that Venus’s stratosphere would be at least 44K hotter if it had a N2-O2-dominated atmosphere and much lower CO2 concentrations like Earth.
CO2 cannot change atmospheric temperature in any case. Causes must always precede effects, and CO2 levels in the atmosphere follow temperature change on all time scales. Half a dozen recent studies, including one intended as disproof, confirm the lag described in Humlum & al’s original 2013 research. CO2 levels are an effect, not cause, of temperature change.
The foregoing is not anomalous. All have been confirmed by replication.
Remember also, CO2 is about 400 parts per million by volume of our atmosphere. That is 0.04% of the atmosphere. Human-generated CO2 by IPCC estimate is about 5% of that. In money terms, 0.04% of $1,000 is 40ȼ, with people’s share 2ȼ.
Reply