I have a keen interest on the topic of pollution, my dissertation is focused around water pollution and plastic pollution. To widen my knowledge in regards to global environmental change caused by pollution I have chosen the topic of black carbon. Although CO2 has a greater climate forcing meaning it is the most important human emission, black carbon actually comes after CO2 in terms of impact and importance with a forcing of +1,1 W m - 2.
Below is a short clip explaining Black Carbon and why it is important.
This first blog will give a brief insight into black carbon and its effects.
This first blog will give a brief insight into black carbon and its effects.
Black carbon (BC) is a short-lived climate pollutant created by incomplete combustion, the source can be from natural sources such as from grass/forest fires or caused by humans such as the burning of fossil fuels. Although BC has a short residence time in the atmosphere, at around one to seven weeks, it is a major driver of climate change. BC can travel with the wind for thousands of miles allowing it to be distributed around the globe; this leads to a darkening of snow and ice which can cause increase melting of snow and ice due to the reduction of the albedo effect.
When BC is mixed with other aerosols it causes transcontinental atmospheric brown clouds, which can intercept solar radiation causing global dimming on the earths surface, affecting the hydrological cycle.
BC is a component of soot which is made up of microscopic particles that mostly contain BC, organic carbon and sulphur. Figure 1 shows how BC in soot absorbs both incoming and reflected sunlight, therefore leading to global dimming. In addition the particles also cause the scattering of sunlight entering the atmosphere therefore less ultraviolet radiation makes it to the surface of the earth leading to cooling.
Figure 2 shows an example of soot emissions from a diesel bus in the uk, the black element that makes up the smoke is black carbon. There is also is a lot of bad press at the moment around diesel vehicles which I hope to cover in future blogs.
The aim over the coming weeks is to gain a greater depth in understanding of and the issues surrounding Black Carbon, and the impacts that it is creating for the environment and our health. Being a highly relevant topic, I will try to cover as much as possible, whilst extending mine and your knowledge of this topic.
* Click the hyperlinks to read in more depth or to access the sources.
Figure 1, source Bachmann J, (2009)
BC is a component of soot which is made up of microscopic particles that mostly contain BC, organic carbon and sulphur. Figure 1 shows how BC in soot absorbs both incoming and reflected sunlight, therefore leading to global dimming. In addition the particles also cause the scattering of sunlight entering the atmosphere therefore less ultraviolet radiation makes it to the surface of the earth leading to cooling.
Figure 2 shows an example of soot emissions from a diesel bus in the uk, the black element that makes up the smoke is black carbon. There is also is a lot of bad press at the moment around diesel vehicles which I hope to cover in future blogs.
The aim over the coming weeks is to gain a greater depth in understanding of and the issues surrounding Black Carbon, and the impacts that it is creating for the environment and our health. Being a highly relevant topic, I will try to cover as much as possible, whilst extending mine and your knowledge of this topic.
Figure 1, source Bachmann J, (2009)
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