Nav: Home

Current atmospheric models underestimate the dirtiness of Arctic air

May 25, 2016

Black carbon aerosols--particles of carbon that rise into the atmosphere when biomass, agricultural waste, and fossil fuels are burned in an incomplete way--are important for understanding climate change, as they absorb sunlight, leading to higher atmospheric temperatures, and can also coat Arctic snow with a darker layer, reducing its reflectivity and leading to increased melting. Unfortunately, current simulation models, which combine global climate models with aerosol transport models, consistently underestimate the amount of these aerosols in the Arctic compared to actual measurements during the spring and winter seasons, making it difficult to accurately assess the impact of these substances on the climate.

To find out if these inaccuracies could be mitigated, a team of scientists decided to use the Japanese K computer to perform fine-grained simulations of how black carbon aerosols are transported to and distributed in the Arctic region. By using smaller grids--with spacing of just a few kilometers rather than several tens of kilometers as in conventional current models--they were able to show that they could more realistically model the amount of black carbon aerosols, mitigating the underestimation in more coarse-grained models. Their finest model used 3.5 kilometer grids broken up vertically into 38 layers, so that it required 1.6 billion grids to cover the globe. The simulation, done on the 10-petaflop K computer, still required 17 hours to perform the two week simulation.

According to Yousuke Sato of the RIKEN Advanced Institute for Computational Science (AICS), "this research shows that powerful supercomputers, by performing more fine-grained simulations, can help us to model weather and climate patterns in a more realistic way. We have to note, however, that while our model reduced the underestimation, it did not completely eliminate it. Further generations of even more powerful computers will allow us to run simulations that may be able to make even more realistic simulations and help us to understand the mechanism through which these aerosols are transported."

"It is also known," continues Sato, "that current models do not realistically model the vertical distribution of the aerosols, and we believe that finer measurements could help there as well. Unfortunately there were no vertical measurements taken in November 2011, the time we chose to model, so we plan in the future to do simulations for time periods for which actual measurement data exist."
-end-
The research, published in Scientific Reports, was carried out by AICS in collaboration with the University of Tokyo, the National Institute of Environmental Studies, Kyushu University, and the Japan Aerospace Exploration Agency.

RIKEN

Related Aerosols Articles:

Human activities worsen air quality in Dunhuang, a desert basin in China
Due to the increasing contribution of human activities, air quality has become worse in the most recent decade over the Dunhuang area, and the main reason is a shift to a mixture of coarse and fine particles, having previously been due to dust aerosol alone.
Role aerosols play in climate change unlocked by spectacular Icelandic volcanic eruption
A spectacular six-month Icelandic lava field eruption could provide the crucial key for scientists to unlock the role aerosols play in climate change, through their interactions with clouds.
Large volcanic eruption may have caused the first mass extinction
Researchers say they may have found the cause of the first mass extinction of life.
Biological activity found to affect aerosols produced from sea spray
Chemists have discovered that tiny particulate matter called aerosols lofted into the atmosphere by sea spray and the bursting of bubbles at the ocean's surface are chemically altered by the presence of biological activity.
Exploring ocean waters to characterize atmospheric aerosols
Aerosols play a major role in cloud formation, with a strong impact on climate models.
Air pollution may have masked mid-20th Century sea ice loss
Humans may have been altering Arctic sea ice longer than previously thought, according to researchers studying the effects of air pollution on sea ice growth in the mid-20th Century.
Rocky mountain haze
University of Utah atmospheric scientist Gannet Hallar and colleagues find a correlation between the severity of drought in the Intermountain West and the summertime air quality, particularly the concentration of aerosol particles, in remote mountain wilderness regions.
New insights into how black carbon aerosols impact the atmospheric boundary layer
It is widely known that soot particles emitted from South Asia are spread across the northern Indian Ocean during the winter monsoon season.
Aerosol emissions in East Asia driven by consumption in developed countries
Much of the influence on climate from air pollution in East Asia is driven by consumption in the developed countries of Western Europe and North America, according to research co-led by McGill University atmospheric scientist Yi Huang.
Aerosols strengthen storm clouds, according to new study
An abundance of aerosol particles in the atmosphere can increase the lifespans of large storm clouds by delaying rainfall, making the clouds grow larger and live longer, and producing more extreme storms, according to new research from the University of Texas at Austin.

Related Aerosols Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".