Black Carbon policy 2: My thoughts.

Only in the past few years have we begun to see the integration of black carbon into policy. Reduction of sea ice, within the Arctic, is becoming ever pressing and require the movement of policies from move from local legislations onto the global platform, in order to reduce BC emissions. There is a substantial body of scientific research explaining why BC policies should be put in place, so why is there a gap between the science and the implementation of global policies? Within this post I aim to reflect and discuss some of the thoughts I have had surrounding this topic of Black Carbon and the related polices in response to a  recent article in the Nature Journal.

Is this how we are viewing climate change?
We know BC is causing warming. So why are we not acting?

Heath- a motivator for change?

For many reducing Black Carbon for the sake of the Arctic is not a huge motivator. Health implications, associated with BC, are more of an encouragement to other global bodies to promote emission cuts. For example if the BC production was halved by 2030 approximately, 2.4 million premature deaths a year could be avoided.

However, the House of Commons Audit report (addressing the threats to the Arctic) states “Black carbon is a climate and health problem. If policy makers continue to consider black carbon as only a health and air quality problem we will fail to optimise the climate and Arctic benefits from Black carbon”. For policies to be beneficial, political bodies must first recognise the climatic issues of BC (as well as the health issues) and then incorporate this into the decision making process.

Climate and Air quality polices.

Furthermore, whist researching both climate change and air quality policies (which BC would fall under) all I seem to find is a contradiction. An example of this is biomass burning. The burning of biomass reduces Carbon Dioxide in the atmosphere but causes a greater volume of Black Carbon to be released. This just seem madness to me! Policies combating climate change and BC need to walk hand in hand (eg. Switching to renewable energy sources) as opposed to many of the ‘either-or’ decisions currently in place.

Agree or even disagree with my thoughts? Let me know by commenting!

Black Carbon Policy 1: Wherefore art thou

As with any environmental issue, policies are implemented to mitigate and prevent any further damage. Yet black carbon is yet to be the latest craze for policy makers. Highwood and Kinnersley (2006) argue mitigating Black Carbon (BC) emissions has the potential to act as a short term fix for global warming. If this is the case then why are global policy makers not incorporating this form of pollution?

International Long Range Pollution policies.

Long Range Pollution was introduced to international climate policies in 1979. The Geneva Convention on Long range Transboundary Air Pollution was signed in 1979 and implemented in 1983, being the first policy which recognized the issues of transported pollutants. The most recent international agreement, the Gothenburg Protocol implemented in 1999, set limitations on aerosols (sulphur dioxide and nitrogen oxides), organic compounds and ammonia to be achieved by 2010. Upon completion Europe aimed to reduce sulfur emissions by approximately  63% (in comparison to 1990).

A further policy which focuses on long range pollution is The Climate and Clean Air Coalition, which consists of a series of governments, civil societies and private sectors from countries including Bangladesh, Mexico and the US. The coalition targets methane, Black Carbon and HFCs by raising awareness of these short lived climate pollutants.

Despite this recent incorporation of BC across several political innovations, the pollutant still seems to be lacking across the global environmental scene.The IPCC 5^th report (published in 2013) introduced aerosols and their radiative influences for the first time, yet Black carbon is still nowhere to be seen. It is the incorporation of BC into these global policies and research studies, such as the IPCC, which will help to reduce emissions.

Within the Arctic.

Black carbon in Yukon.
 Should the Arctic really be looking
like this? 

Policies still seem to be few and far between. To combat this issue of long range BC such policies must be integrated on a global scale, and not just by the countries who will come off worse! It seems many of the international climate debates are focused on Green House Gases and ignoring most other forms of pollution. In order to reduce BC emissions and benefit the Arctic this must change! 

Black carbon is a more pressing issue within the Arctic for reasons discussed within my previous post. As a result of this a greater number of policies incorporate black carbon reduction in their plans. The Arctic Council, in particular, play a large role in addressing the issues of black carbon. The Council’s most recent report discusses a framework of action, in which they aim to raise awareness of the black carbon as a climate issue and include stakeholders and national governance in the implementation of international mitigation agreements. Recently, members from the Arctic were present at the COP21 debates, where they spoke about the role of BC in the Arctic. However GHG’s remained the pressing feature of the conference (nothing new there!). Despite the work undertaken by the Arctic Council, still only Norway has developed a national specific plan to reduce SCLPs (Black carbon included within this).

Black carbon: The dark horse of global warming

“Arctic haze is made up of a complex mix of microscopic particles and acidifying pollutants such as soot, hydrocarbons, and sulphates”

Arctic Haze if one of the main effects of Long range aerosols in the atmosphere. 90% of haze consists of sulphate and nitrate particles and the reaming consists of black carbon and hydrocarbons. What really interests me is the warming effects caused by black carbon (or soot) in the Arctic region. Black carbon sits at the other end of the spectrum to reflective aerosols (such as sulphates), absorbing solar radiation and warming the surface temperatures.

The picture shows the impacts black carbon
(and other aerosols) can cause on limestone buildings.

BC is caused by the incomplete combustion of organic matter (including either organic matter, from forest fires, or anthropogenic, as a result of fossil fuel combustion) and consists of 5-10% of particulate matter found within urban areas in the US and Europe. Across the globe, black carbon can have detrimental impacts on local climate and health. This is particularly an issue in Venice where buildings are falling victim to the deposition of black carbon.

Warming, caused by black carbon, is particularly profound in the Arctic region due to the sensitivity of feedback systems which occurring there. Black carbon, within Arctic haze, absorbs incoming infra-red and converts this to ultra violet radiation, resulting in warming. Deposition of BC also reduces albedo (lowering the ability of the snow covered surface to reflect) and absorbs radiation (directly on the surface) therefore creating localized warming. Such reduction in albedo can have similar climatic effects as GHGs, in terms of summer sea ice reduction. Highwood and Kinnersley (2006) challenge this by stating the direct forcing of aerosols could make changes of 0.5Wm-2, which only accounts for approximately 1/3 of the warming caused by carbon dioxide and other greenhouse gases. The degree of warming is still uncertain but it is certain that BC is contributing to climate change.

Other, indirect impacts of BC can alter the properties of clouds. When combined with sulphates, in the atmosphere, black carbon can also influence the size of water droplets in clouds.

Furthermore, black carbon particulates can pose as carriers for other toxins. There surface area (of carbon particulates) provide an area for other chemicals, such as polycyclic aromatic hydro carbons, to rest upon and be transported into the lungs. Koelmans et al (2006) argues the presence of BC may be positive. Their paper states the presence of this particulate can make toxic chemicals (on the surface of BC) less available for biota. So maybe it isn’t all bad! However both black carbon and the chemicals transported on its surface, can have serious health implications for humans and other mammals in the region.  

So remember, whilst you are sat in front of your roaring fire this Christmas, the black carbon produced could be causing the Arctic to melt… Leave a comment with your thoughts! 

Sulphates: The light in the dark

Not all aerosols warm. Sulphate particles, for example, can cause a dip in surface temperatures as a result of their ability to reflect infra-red radiation. For geoengineering purposes (Solar radiation management) or a “quick fix” against climate change, sulphates have provided a shining light as a new method to combat rising temperatures. Aerosols, injected into the atmosphere, reflect solar radiation back into space, thus preventing it reaching the earth’s surface. This is hoped to contradict the warming effects of greenhouse gases.

Najafi et al (2015)

So back to the Arctic…

Warming is occurring at an amplified rate within the Arctic. A study recently published in Nature Climate Change suggests aerosols could be used as a method of slowing the rising temperatures. The paper highlights the ability of aerosols to scatter radiation and cause clouds to form. Modelling results suggests greenhouse gases were going to cause a 3 degrees Celsius warming over the Arctic, yet the rise in temperature currently stands at only 1.2. The difference between predicted and observed can be accounted to the cooling influence of sulphates. This demonstrates the potential of SRM schemes, especially in the Arctic.

It is important to remember SRM, as a method of mitigating climate change, does not come without risks. A friend of mine covers the topic of Solar Radiation Management in her blog and highlights the risks associated with this type of geoengineering. Aerosols only influence the climate for approximately 2 years before being removed, from the atmosphere, by precipitation. A greater concentration of sulphates can result in a lower pH rainwater (acid rain). Secondly, the uncertainty associated with these methods is still high and the failure of these schemes could subject the earth to rapid warming, at a greater rate and to higher temperatures than current.

Thoughts:

Before I began engaging with the literature surrounding this topic I recorded my initial opinion as I was interested to see if it had changed: “I believe geoengineering is not a good mitigation strategy. Messing with the natural climate system will only end badly and the negative impacts of aerosols (in the Arctic especially) has not been considered holistically. Based on what I have read this is not going to be a long term fix for climate change. In the Arctic, aerosols have a series of negative effects including changes to the composition of clouds, which has not been considered.”

I started this blog seeing all types of pollution as negative, but after reading this I have been shown that aerosols are not all bad. Any method which can slow the warming in the Arctic must be positive! However the future isn’t so bright. Predictions show anthropogenic productions of aerosols are predicted to decline (whilst greenhouse gases continue to rise), indicating rate of warming within the Arctic will increase in the near future.

This is a very controversial topic and I would be very interested to hear your opinions so please comment and let me know! 

Would you stop using deodorant to save the Arctic?

Scientific topics tend to dominate the discussions of long range pollution so I thought I would divulge away from this for a week and focus purely on the use of spray aerosols deodorants. Deodorant is part of everyone’s morning routine (or so I would hope!) but I doubt many of us consider the environmental impacts associated with the product.

The canned deodorants use aerosols (such as Nitrous oxides) to propel the product out of the can. Previously, CFCs were used but after the negative effects (depleting ozone) were established, companies moved to aerosols thinking they were a better alternative... I have touched upon both the direct and indirect impacts of aerosols in the Arctic now and can conclude they are having a series of negative effects on the Arctic’s climate. Switching from spray deodorant could be just one of the things YOU could do to reduce aerosol emissions. 

Implementing change

As with any environmental policy there are debates to who should be responsible for implementing change. One option is encouraging a bottom up approach and ‘leave it to the people’. Dryzek (2012)* argues people need to give up cherished ideas to project the environment and us as individuals need to make conscious decisions to become more environmentally aware.

However in order for this to be successful you would need to change a series of social practices which are embedded in daily our routines. An example of this is the use of spray deodorants. There are several reasons why this may be difficult, creating what is referred to as the value action gap. Firstly many people would struggle to conceptualize the idea that spray cans could be causing warming in the Arctic, this removes the motivation to change. Secondly, many individuals dismiss that changing a small aspect of their daily routine may be able to make a difference; many believe a single persons actions will not be able to combat such large scale problems.

Ironic eh? But i thought this image demonstrated the issue
 of the Value Action Gap pretty well... why are our intentions
so different from our actions? 

Personally, I don’t feel I will be receiving the same antiperspirant protection from role on as I do from spray deodorant. Smelling, in today’s society, is viewed as totally unacceptable and this fear keeps me reaching from my spray can every time. These factors will make it very hard to persuade the average consumer to make such a change for the sake of the Arctic and continue to fuel this value action gap.  

Despite being an interesting topic, the impacts of spray cans cannot be compared to the large influx of aerosols from other sources. Aerosols can originate from a range of sources including smoke produced by tropical forest fire and burning of fossil fuels. Production of aerosols is concentrated in the northern hemisphere, mirroring extensive industrial activity. Rhan (1980) argues aerosols found within the Arctic are primarily from Eurasia, with small proportions also from North America and Eastern Asia. Now I know this reference is old, but this just illustrates aerosol pollution is a long standing problem which still remains today. Fisher et al. (2011) supports this by also stating large volumes of aerosols “from East Asian and European anthropogenic sources… growing contribution from North America”. However, since this reference was written, aerosol production in Asia and Europe began to decline following the introduction of clean air policies.

Remember...It is important to note I am looking at aerosols as a whole in this post, varying types (sulphates and black carbon for example) all have individual sources. For example large volumes of black carbon is produced from burning boreal forests; however in relation to the total amount of aerosols in the Arctic this volume is minor.

So the question still stands… Would you stop using deoderant to save the Arctic? (Comment and let me know!)

*Dryzek, J.S. 2012. The Politics of the Earth, Oxford University Press, Oxford

Clouds: The innocent bystanders of long range pollution

So carrying on this long range pollution theme, and a particular focus on Aerosols, I wished to burrow deeper into the literature of the impacts of aerosols in the Arctic. Within this post I aim to open your eyes to another impact, in the Arctic, which you may not have heard about before; the impacts of aerosols on clouds.

Sulphate aerosols, in particular, can alter the micro-physical properties of clouds. "Aerosols in the lower atmosphere can modify the size of cloud particles, changing how the clouds reflect and absorb sunlight, thereby affecting the Earth's energy budget". Changes in the energy budget have played a role in causing amplified warming in the Arctic. Kay and Gettelmen (2009) argue that feedback systems, created by changes to cloud composition, can be held accountable for the great loss of sea ice during the 2007 event.

I bet you don’t think about the clouds when you think of the impacts of
 long range pollution in the poles, do you?

Impacts of aerosols on clouds

A series of complex interactions link clouds, aerosols and sea ice in the Arctic. Aerosols can act as both a warming and cooling agent in this case. Clouds, in the Arctic, can also have “an annual-mean net warming effects on the Arctic surface”. When surface temperatures are cooler than internal temperature of low clouds, infra-red radiation emitted from clouds, warms the surface. The presence of long range aerosols can alter the mirco-physical properties of the clouds and consequently alter the annual net energy budget (this factor is often ignored when modelling Arctic change). This influence on the natural energy budget is refereed to as the aerosol indirect effect.

Changes to the effective radius of water droplets can have varying implications of the surface energy budget. Optically thin spring time clouds typically contain low droplets concentrations. The presence of aerosols causes a greater number of smaller water droplets, consequently optimizing longwave emissivity of clouds and increasing surface warming. A 50% change in the radius of water droplets can alter the energy budget by 40 W m^-2.  

In many cases a mixture of aerosols black carbon can increase water droplet size, within the cloud, thus increasing the albedo of clouds and causing surface cooling. However, this is minimal in comparison to the warming influence of clouds, as they already sit above a highly reflective surface (ie snow) (Graversen et al., 2008). 

Sensitivity and Meteorological conditions

Tietze et al. (2011) illustrated the sensitivity of clouds, to long range aerosols, by analysing changes to properties including liquid cloud effective radius and optical depth. Pollutants were identified to have the biggest impact around the freezing point, sensitivity decreases above or below these temperatures. Results also indicated the optical depth was up to 4 times more sensitive (than effective radius) to the presence of aerosol pollutants. This difference was attributed to an unknown feedback system.  

However, simply looking at the properties of clouds does not create a true representation of the systems in the Arctic. To get a true picture, when modelling the influence of aerosols, meteorological conditions should also be incorporated. This is illustrated by the results of Coopman et al. (2015) who contradicted Tietze et al, by stating optical depth and liquid cloud effective radius have very similar sensitivities to aerosol pollution (under similar conditions). Furthermore, localised meteorological conditions influence the extent to which aerosols alter certain properties (increased water vapour within the air can increase the impact of aerosols on cloud sensitivity). Differences in meteorological conditions can also account for the differences between optical depth and effective radius found within the Tietze et al. study.

High levels of uncertainty are associated with modelling studies in the Arctic. I have noticed a there is a large gap between firstly the simulated and observed results and also little consistency between the results of different studies. This uncertainty can often be associated with changes in cloud properties. In particular, the influence of meteorological conditions are often not considered and the incorporation of the scientific knowledge (discussed above) will help reduce such uncertainty.

The future of The Arctic

In my last post (which post I hear you say? You haven’t read it? Well do so NOW!) I described the effects of Aerosols on the Arctic regions, what I failed to touch upon was how such effects will influence the Arctic in the region.

Law and Stohl (2007) conclude their paper by exploring these future changes. It has been suggested, by 2040, Arctic summers will be ice free (Roach, 2006). Such changes could have huge implications on the distribution of aerosols pollution. Firstly, a greater area of open ocean could result in greater production of natural Sulphate aerosols. Furthermore ship traffic, within the Arctic region, can be held responsible for rising levels of summer pollution. As volumes of summer sea ice decrease (due to localised pollution and warming) larger areas of the sea become open to shipping transport, resulting in the deposition of soot. Thus, reducing albedo, creating a positive feedback system and further ice melt (I will cover the effects of black carbon deposition at a later date do sit tight!).

The Arctic dome is also anticipated to weaken in the future as regional temperatures rise. Consequences of this may include increased levels of pollution from southern Asia, from which pollutants are currently too warm and moist to preach this barrier. The paper proposes that such movement of pollutants could be facilitated by an “upward trend in the North Atlantic Oscillation”. This factor needs to be considered when implementing policies (for reducing long range pollution) in the Arctic, as the potential geographical sources, of pollution, will increase with rising temperatures (Law and Stohl, 2007).

Thoughts:

Many of these feedback systems created by pollutants, such of aerosols, will only intensify in the future. As always uncertainty must be accounted for in climate change predictions, but the evidence for melting Arctic sea ice is currently present and, surely, this will continue as feedback systems intensify.

In order to combat these changes, the concentration of atmospheric pollutants need to decrease. This should not be purely focused in north Eurasia (the source of the majority of current long range pollution in the Arctic) but include southern latitudes also. The reduction of pollutants, especially short lived pollutants such as black carbon, could dramatically decrease rates of ice loss in the Arctic. It is important not to just focus on the famous GHGs as other pollutants are having as detrimental influences on the Arctic and must also be reduced to prevent large scale global warming.