It is clear that increasing greenhouse gas emissions is a major contributor to global warming. However, several other factors are known to work at the local level rather than the entire planet.
Especially in the Arctic. The vast oceanic regions around the Arctic are warming two to three times faster than other parts of the planet.
As the polar ice cap melts, the albedo, the surface ability to reflect a certain amount of solar radiation, decreases. When viewed from above Earth, bright surfaces such as glaciers, snow and clouds have a high rate of light reflection.
Therefore, as the albedo decreases as snow and ice decreases due to warming, more solar radiation is absorbed by the Earth, causing temperatures near the surface to rise.
Diagram showing climate-related aerosol processes during polar nights in the Arctic. INP is an ice nucleation particle, IR is infrared. Red arrows indicate long-wave radiation. © EERL
Aerosols, essential for climate control
There are also more complex regional factors different from albedo. The way clouds and aerosols interact, it is noted that scientists need to pay more attention.
Aerosols, small particles floating in the air, vary in size and composition. Aerosols can occur naturally, such as seawater sprayed into the air, the release of marine microbes, and wildfires in northern regions such as Siberia, and can be produced by human activities such as the use of fossil fuels or farming.
Without aerosols, no clouds are created. This is because water molecules attach to the surface of the aerosol and form water droplets, creating clouds.
Aerosols, along with this role, and more specifically because of their impact on the amount of solar radiation reaching the Earth’s surface and escaping terrestrial radiation from the Earth, are considered essential components of global climate and Arctic climate control.
The figure shows where the average temperature in the Arctic region between October 2010 and September 2011 is 2 degrees Celsius or more above the long-term average (1981 to 2010) (red) or below (blue). Data based on NCEP/NCAR reanalysis of near-surface abnormal temperatures prepared by NOAA’s Earth Systems Research Laboratory. © WikiCommons / Hunter Allen and Richard Rivera (NOAA’s Climate Program Office)http://www.climatewatch.noaa.gov/article/2011/arctic-warming-exceeds-global-average
Still many questions
Dr. Julia Schmale, head of the Extreme Environment Research Laboratory (EERL) at the Federal Institute of Technology Lausanne (EPFL), Switzerland, said in a paper published on the 8th of’Nature Climate Change’, the scientific community has discussed these aerosol-related processes. It suggested that there is a need for further understanding.
Dr. Shumal said, “How albedo is affected by ice is fairly well understood, with the maximum and minimum values set,” he said. “However, there are many variables to consider in aerosol groups.”
In other words, whether it will reflect or absorb light, whether it will form a cloud or not, whether it is natural or artificial, whether it will stay in an area or fly away, there are many questions, and an answer must be found.
The German research icebreaker Polarston is anchored near Reykjavik, Iceland. © WikiCommons/Bruce McAdam
Experience the change of the Arctic on an icebreaker
Assistant Professor Schmal wrote a thesis in collaboration with Paul Zieger, Assistant Professor at the Bolin Climate Research Center at the University of Stockholm and Professor Annica ML Ekman.
In early 2020, Dr. Schmal conducted several expedition studies in the Arctic aboard the German icebreaker Polarstern. At this time, I experienced firsthand that the Arctic climate tends to change the fastest in winter, even though it is a winter with no sun all day and no albedo.
But scientists still don’t know exactly why. One reason for winter’s Arctic climate change may be that winter clouds reflect Earth’s heat back to the ground. This phenomenon occurs to varying degrees depending on the amount of aerosol in the air and the natural circulation.
This phenomenon raises the temperature above arctic ice, but the process is very complex due to the wide range of aerosol types and differences in their ability to absorb and reflect light.
“In the winter months, research in the Arctic requires mobilization of icebreakers, scientists, and equipment throughout the season, so few observations have been made.”
Arctic warming is melting ice and the survival of polar bears is at risk. © WikiCommons / Arturo de Frias Marques
Need to improve climate model
Scientists have already done a lot of expedition research in the Arctic, but it is known that there is still a lot to do. One of them is to collect all the data discovered so far on Arctic warming and use it to improve existing weather models.
Dr. Shumal warned, “A great deal of research has to be focused right now, otherwise you will be one step behind in understanding what is happening.”
“What we’ve already observed can be used to improve the model.”
For example, current climate models do not know whether the aerosols that have the greatest impact on climate change are naturally occurring locally or artificially.
Cloud-making aerosols are known to be an essential component of climate control. Ash particles floating in the air taken with a scanning electron microscope (SEM).
“Aerosol has a great impact on climate and human health”
In their paper, the research team proposed three steps that could be taken to gain better insight into the Arctic climate and the role of aerosols.
The first is to create an interactive, open source virtual platform that can weave all of the Arctic-related knowledge we have acquired so far. An example was the International Arctic Systems for Observing the Atmosphere (IASOA) program.
The IASOA is responsible for coordinating individual Arctic observatory activities to provide an international network of mutual cooperation for Arctic atmospheric research and operations.
“We need to improve our climate model because what happens in the Arctic will eventually affect the whole planet,” said Dr. Schmal. “As we saw the Greenland glaciers melt and sea levels rise, (the Arctic situation) “It is already affecting the climate in other parts of the northern hemisphere.”
“It is important to better understand the role of aerosols in order to develop better climate models,” said Dr. Schmal.
(715)