by P. Gosselin, Nov 26, 2021 in WUWT
Die kalte Sonne reports on a new aerosol study by Liu et al.
The results are a major blow to the high greenhouse-gas climate sensitivity modelers.
IPCC scientists have a favorite wild card they often use to explain serious model discrepancies: aerosols. Mysterious cooling events in the past are often explained away by aerosols from major volcanic eruptions, for example. They act to filter out sunlight.
ccording to IPCC climate models, the mean global temperature should have risen by 1.5°C since 1850 due to the higher CO2 concentrations. But best estimates show that it has instead risen by only 1.1°C. So what about the missing 0.4°C?
Naturally, the missing 0.4°C of warming since 1850 gets explained by the higher 20th century aerosol levels in the atmosphere – due to the burning of fossil fuels. Air pollution by man over the course of the late 19th century and entire 20th century are said to have dimmed the earth, and thus this explains the 0.4°C less warming.
Surprise: global aerosol emissions have been flat over past 250 years
But now results by a new study appearing in the journal Science Advances by Liu et al tells us that the forcing by aerosols had to have been overestimated by climate modelers. IPCC modelers insisted that 20th century aerosol concentrations were higher than during the pre-industrial times, and this is what kept the climate from warming by 1.5°C.
According to the scientists led by Liu, however, atmospheric aerosols in the preindustrial times were just as high as they were just recently. They were in fact more or less constant over the past 250 years. No change means it could not have been aerosols putting the brakes on temperature rise:
That’s a real embarrassment for the IPCC modelers. It means CO2 climate sensitivity has been overestimated.
by University of Helsinki, Dec 10, 2020 in WUWT
Large amounts of new particles can form in the valleys of the Himalayas from naturally emitted gases and can be transported to high altitudes by the mountain winds and injected into the upper atmosphere.
The emitted particles may eventually affect climate by acting as nuclei for cloud condensation. These new findings about particles formation and sources will contribute to a better understanding of past and future climate.
“To understand how the climate has changed over the last century we need to know as reliably as possible the natural atmospheric conditions before the industrialization,” says Associate Professor Federico Bianchi from the University of Helsinki’s Institute for Atmospheric and Earth System Research (INAR).
In order to do that scientists are looking for pristine locations around the world where human influence is minimal. An international group of researchers has now completed a comprehensive study at the Nepal Climate Observatory at Pyramid station, located in the proximity of the Everest base camp at 5050 m above sea level. There, they were able to investigate the formation of atmospheric particles far from human activities. The results were published today in the prestigious journal Nature Geoscience.
by Buel Henry, May 26, 2015 in WUWT
Anthropogenic emissions of SO2 into the troposphere peaked during year 1972 at about 131 Megatonnes. By year 2000, due to worldwide Clean Air Act efforts, SO2 emissions in the West had decreased by approximately 48 Megatonnes. However, during the same time period, emissions elsewhere rose by 23 Megatonnes, for a net worldwide decrease of 25 Megatonnes.
Figure 1: Global sulfur dioxide emissions by region (North Amer- ica = USA,Canada; East Asia, Japan, China, and South Korea). J.Smith et al., Fig 6.
It also proves that the IPCC “Graph of Radiative Forcings” is completely incorrect, since it does not include any warming due to the removal of dimming-aerosols from the atmosphere. To be correct, this forcing needs to be included (which will have the effect of completely eliminating any forcing due to CO2). As noted above, all of the warming can be accounted for by the reduction in SO2 emissions.
by D. Rosenfeld et al., February 8, 2019 in Science
Reflections on cloud effects
How much impact does the abundance of cloud condensation nuclei (CCN) aerosols above the oceans have on global temperatures? Rosenfeld et al.analyzed how CCN affect the properties of marine stratocumulus clouds, which reflect much of the solar radiation received by Earth back to space (see the Perspective by Sato and Suzuki). The CCN abundance explained most of the variability in the radiative cooling. Thus, the magnitude of radiative forcing provided by these clouds is much more sensitive to the presence of CCN than current models indicate, which suggests the existence of other compensating warming effects.
by P. Gosselin, January 27, 2019 in NoTricksZone
Leipzig, 20 December 2018
Researchers from Leipzig cooperate with scientists from Punta Arenas (Chile) to learn more about the relationship between air pollution, clouds and precipitation.
Leipzig/Punta Arenas. How do airborne particles, so-called aerosols, affect the formation and life cycle of clouds and precipitation? In order to come one step closer to solving this question, atmospheric scientists from the Leibniz Institute for Tropospheric Research (TROPOS) and the Leipzig Institute for Meteorology (LIM) at Leipzig University will observe the atmosphere at one of the cleanest places in the world for at least a year. The choice fell on Punta Arenas because the city is located on a comparable geographical latitude as Germany and will thus enable comparisons between the northern and southern hemispheres. The measurement campaign is part of the International Year of Polar Prediction (YOPP), which aims to improve weather and climate forecasts for the polar regions through intensive measurements.
by Prof. H. Svensmark, January 22, 2019 in NoTricksZone
Danish Professor Henrik Svensmark is a leading physicist of cosmic radiation. At the end of last year he made a presentation at the 12th International Climate Conference in Munich, where he demonstrated that the climate is indeed modulated in large part by cloud cover, which in turn is modulated by solar activity in combination with cosmic rays.
His theory is that cosmic rays, which are extremely fast-flying particles – which originate from dying supernovae – travel through the cosmos, strike the Earth’s atmosphere and have a major impact on cloud cover and thus climate on the Earth’s surface.
This, Svensmark says, has been confirmed in numerous laboratory experiments.
by Michigan Technological University, October 2, 2018 in ScienceDaily
… “Wildfires are such a huge source of aerosol in the atmosphere with a combination of cooling and warming properties, that understanding the delicate balance can have profound consequences on how accurately we can predict future changes,” says Claudio Mazzoleni, professor of physics, and one of the authors of the paper.
As wildfires increase in size and frequency in the world’s arid regions, more aerosol particles could be injected into the free troposphere where they are slower to oxidize, contributing another important consideration to the study of atmospheric science and climate change.
by Anthony Watts, March 27, 2018 in WUWT
A new paper published by NASA by Tsigaridis and Kanakidou suggests that climate models have missed the forcing effects of organic aerosols, such as VOC’s from trees, oceans, and other sources that combine chemically in the atmosphere to create new compounds. Known as Secondary organic aerosols (SOA), they say “SOA forcing could exceed that of sulfate and black carbon”.
by University of Leeds, December 4, 2017 in ScienceDaily
Scientists have quantified the relationship between natural sources of particles in the atmosphere and climate change. Their research shows that the cooling effect of natural atmospheric particles is greater during warmer years and could therefore slightly reduce the amount that temperatures rise as a result of climate change.Share: