Probably the most obvious manifestation of air pollution comes when looking out of the window and scanning the horizon – does the landscape go on for miles or is the view reduced? The build-up of air pollution can often dramatically reduce visibility via a shroud of haze. On a recent trip to the Turkish Mediterranean coast near Antalya, the impact of air pollution on visibility was abundantl ...[Read More]
Do you think that’s air you’re breathing?
Air pollution has been a major issue in our atmosphere since the Industrial Revolution, with the smoke emanating from the many factories leading to smog settling over our cities and countryside. The author Johanna Schonpenhauer remarked in 1830 that Manchester was: Dark and smoky from the coal vapours, it resembles a huge forge or workshop. As industrialisation and motor vehicles spread across the ...[Read More]
Cooking up some aerosol
Ever wondered how many aerosol particles are emitted by microwaving popcorn? Or how polluted a football match is? I’m going to assume your answer is no but it turns out that science has the answer anyway! Outdoor air pollution is a significant concern but air pollution indoors and in other enclosed spaces is of comparable importance. A US study estimated that around half of our exposure to a ...[Read More]
An aerosol is born: solving the nucleation recipe
One of the most fundamental aspects of aerosols that we are continually striving to understand is how they are actually born. One pathway that aerosol particles can take is a process known as “nucleation“. This nucleation process is where new particles are formed by gaseous molecules getting together and deciding that they’ve had enough of the gas-phase and would prefer to be tin ...[Read More]
The role of aerosol uncertainty in climate change
For those who follow [pun intended] the world of climate science on Twitter, you’ll very likely have noticed a string of tweets from a meeting at the Royal Society on the “Next steps in climate science“. The programme (PDF here) has included a wide range of topics relating to climate science and has included a number of scientists who heavily contributed to the recent IPCC Workin ...[Read More]
Pioneers of aerosol science: John Aitken
One fundamental point on which we have at present little information of anything like a definite character is as to the number of solid particles present in our atmosphere. We know that they are very numerous, and it seems probable the number varies under different conditions of weather; but how many particles are really present under any conditions, and how the number varies, we have at present v ...[Read More]
Biomass burning birthday
Last September I spent a month in Brazil for a research project aiming to study the pollution produced by deforestation fires in the Amazon Basin. The fires are mainly started by people for agricultural needs or land clearing for buildings and infrastructure. These fires produce huge amounts of smoke that blanket vast regions of South America during the “dry” season, which can lead to ...[Read More]
Smoky summers
The past summer has seen a great deal of media coverage of fires burning across the globe. When I consider what to write about for the blog, it has often been difficult to avoid commenting on yet another instance of a fire burning somewhere. This has been especially difficult given my current research project investigates biomass burning aerosol from deforestation and agricultural fires in Brazil. ...[Read More]
Aerosols from space #1
A short post to illustrate the changing nature of aerosol in the atmosphere in terms of their spatial extent, source and properties. There are two images below showing the scene from the TERRA satellite as it passed over the Eastern Atlantic off the coast of Morocco. The first image shows the plume of smoke from wildfires from Madeira that swept through the island last weekend. The second image sh ...[Read More]
Sweeping soot out of the atmosphere
Efforts to slow the rate of global temperature rise in the 21st Century have for some time focussed on non-CO2 species or so-called ‘short-lived forcers’. As far as aerosols are concerned, black carbon (often referred to as soot) has been the main avenue to explore due to its capacity to warm the atmosphere by absorbing sunlight. Black carbon contrasts with most other aerosol species w ...[Read More]