From June 13th to 22nd, 2012, the United Nations Conference on Sustainable Development, Rio+20, will be held in the city of Rio de Janeiro. The main objective of this Conference is to renew the political commitment to sustainable development.
All over the world there is a consensus that progress is needed, but it must go hand in hand - and not to the detriment - quality of life, promoting a safe environment in society. It cannot be denied that the development of technology has had an enormous positive impact on the social and political fields. However, the disorderly growth of cities has also had negative consequences.
One of the biggest environmental problems, which is considered a determinant phenomenon for the future of humanity and an essential element to be considered in the elaboration of public policies and strategies for development, is the gas emission-stove.
Chemistry is involved in this problem, and in its possible solutions as well. To understand how this happens, let's see
what is the greenhouse effect, what are the gases responsible for this phenomenon, what are some related proposals from Brazil for Rio+20 to this issue, and what measures will be taken during the Conference so that it does not contribute to a greater production of greenhouse gases; as usually happens in the preparation and realization of a large event like this.- What is the greenhouse effect:
The Earth works like a big greenhouse. A greenhouse is a closed chamber, whose walls and roof, usually made of glass, allow the sun's rays to enter, but hinder the exit of heat energy. This keeps the environment warm for growing plants in cold places.
The Earth performs a similar mechanism, which keeps the Earth's climate mild without major variations. Our planet receives solar radiation, which upon reaching the earth's surface is reflected in the form of radiation infrared, which would be radiated all the way to space, leaving the Earth cold and with an inappropriate environment for the development of life. However, in the atmosphere there are greenhouse gases, which absorb much of this radiation that is reflected by the surface, warming the Earth.
The greenhouse effect is important for sustaining life. However, what happens is that the concentration of these gases in the atmosphere is increasing more and more, in as a result of human activities (mainly the burning of fossil fuels in industries and vehicles self-propelled). The result is an exacerbation of the greenhouse effect and global warming.
- What are greenhouse gases:
The gases responsible for the greenhouse effect, which absorb infrared radiation and which are being increasingly released into the atmosphere by humans, are: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), ozone (O3), chlorofluorocarbons (CFC's) and hydrochlorofluorocarbons (HCFC's).
Let's see more about the two main ones:
- carbon dioxide (CO2): Better known as carbon dioxide, it is a great villain of the greenhouse effect. To give you an idea, annually about 2 650 billion tons of carbon dioxide are released into the atmosphere. Its average time in the atmosphere is 100 years, which leads us to conclude that for the concentration of this gas in the atmosphere to decrease, large reductions in its emissions are necessary.
In Brazil, the main sources of emission of this gas are burned in forests in the Amazon region, in sugarcane plantations, from savannahs, fields and from the burning of fossil fuels, mainly coming from oil in engines explosion.
- Methane (CH4): It is a hydrocarbon that can form naturally, such as in coal mines and swamps, by plant decay, and by human action, such as in the extraction and use of fossil fuels and in the anaerobic decomposition of organic waste by bacteria that multiply in landfills Sanitary. The emission of this gas is estimated to reach a total of at least 515 million tons per year.
In Brazil, its emission is due to the large quantities of cattle and the presence of extensive regions that are periodically covered by water.
- Brazil's proposals for Rio+20 related to the greenhouse effect:
At the Brazilian Contribution Document to the Rio+20 Conference Brazil's initial visions and proposals on the Conference's themes and objectives are presented. Among them are aspects related to the greenhouse effect. See some:
- Create incentives and promote reforms aimed at expanding the use of renewable energy sources, such as hydroelectric energy, electric energy generation from biomass, wind energy, solar energy, and other non-conventional ones, such as solid residues, microalgae and effluents;
- Improve production technologies for cleaner automotive fuels, encouraging the use of renewable fuels, such as biofuels;
- Use of sanitary landfills for energy production (biogas). The combustion of biogas contributes to reducing the emission of greenhouse gases, by transforming methane (its main component) into carbon dioxide (twenty times less harmful to the environment). In addition, it generates energy, reduces the risk of accidents and increases the quality of life in its surroundings;
- Initiatives to identify the more sustainable companies. The document cited says: “In Brazil, BM&FBOVESPA established, in 2005, the Sustainability Index Corporate, which measures the return on a portfolio of shares of companies with recognized commitment to sustainability. In 2010, the Carbon Efficient Index (ICO2) was launched, which recalculates the IBrX (an indicator composed of the 50 most traded shares on the Stock Exchange) based on companies' greenhouse gas emissions.”
- Management of greenhouse gas emissions during the Rio+20 Conference:
This subject is also part of the agenda of themes for the Rio+20 Conference, and in its preparation there was already a concern with the environmental pollution that could be generated in this event. Therefore, the Brazilian Government created the National Organizing Committee (CNORIO+20), which established a Coordination of Sustainability to analyze possible environmental impacts and propose activities that can reduce or compensate for such impacts.
Among the areas of activity of this Coordination is exactly the emissions of greenhouse gases (GHG). The main aspects being measured are:
- Types of fuels used in land vehicles and fixed equipment;
- Electric energy used at the event venues;
- Waste generated;
- Air travel by accredited delegates and the United Nations secretariat.
The expectation is that the waste and emissions generated will be 5,000 tons, and those that cannot be reduced during the event will be offset through the use of "certified emission reductions" (CERs) from Brazilian Development Mechanism projects Clean (CDM). The Coordination has already identified Brazilian companies that will donate CERs.
In addition, the Rio+20 Sustainability Coordination partnered with Caixa Econômica Federal and with UNDP Brazil, for the use of an application that calculates emissions from air travel. Rio+20 participants will be able to use it to measure their air transport emissions and buy CERs from Brazilian CDM projects and, with that, make the necessary offsets.
More details on these strategies can be seen at the following electronic addresses on the Conference's official website:
- Greenhouse gas emissions
- Greenhouse Gas Emission Management
By Jennifer Fogaça
Graduated in Chemistry
Source: Brazil School - https://brasilescola.uol.com.br/quimica/conferencia-rio20-emissao-gases-estufa.htm