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Knowledge Nugget: 7 Must-Know Environmental Terms

Subject: Environment 

(Relevance:UPSC often asks questions about key environmental phenomena or terms, both directly and indirectly. Thus, having clarity about some important environmental terms becomes important.)

The 29th edition of the Conference of the Parties (COP) began in Baku, Azerbaijan, on Monday (November 11). It is an international climate meeting organised annually by the United Nations. COP is short for Conference of the Parties. ‘Parties’ refers to (now) 198 countries that have joined the international treaty called the UN Framework Convention on Climate Change (UNFCCC). ‘Parties’ to the treaty have pledged to take voluntary actions to prevent “dangerous anthropogenic [human-caused] interference with the climate system.”

In this context, let’s understand some environment-related key terms that will be hitting the headlines regarding COP 29.

Brief History of COP 

In 1992, at the Rio Earth Summit, 154 countries signed a multilateral treaty called the UNFCCC. It aimed to stabilise greenhouse gas concentrations “at a level that would prevent dangerous anthropogenic (human-induced) interference with the climate system.” The treaty came into force two years later, and since then, countries which are part of the UNFCCC, meet every year at different venues.

According to the Intergovernmental Panel for Climate Change (IPCC), “Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.”

Alternatively, UNFCCC in its Article 1, defines the phenomena as ‘a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods.’

It is the amount of greenhouse gases-especially carbon dioxide-released directly or indirectly by an individual or institution into the atmosphere. It refers to the quantity of GHG produced in our daily life as a result of the combustion of fuels for electricity, heating, transportation, and other purposes.

Carbon dioxide retains heat released by both the sun and the earth's surface and releases that heat into the atmosphere. As the burning of fossil fuels and deforestation continues, high concentrations of greenhouse gases, particularly carbon dioxide, threaten to elevate the planet's average surface temperature to unacceptable levels, resulting in life-threatening consequences.

Carbon markets allow the trade of carbon credits with the overall objective of bringing down emissions. These markets create incentives to reduce emissions or improve energy efficiency. They allow countries, or industries, to earn carbon credits for the greenhouse gas emission reductions they make in excess of their targets. These carbon credits can be traded to the highest bidder in exchange for money. The buyers of carbon credits can show the emission reductions as their own and use them to meet their reduction targets.

For example, an industrial unit that outperforms the emission standards stands to gain credits. Another unit that is struggling to attain the prescribed standards can buy these credits and show compliance with these standards. The unit that did better on the standards earns money by selling credits, while the buying unit is able to fulfil its operating obligations.

CCS refers to a host of different technologies that capture carbon dioxide emissions from large point sources like refineries or power plants and trap them beneath the Earth. It is important to note that CCS is different from carbon dioxide removal (CDR), where carbon dioxide is removed from the atmosphere.

Carbon capture, utilisation and storage (CCUS) is a step further than CCS and uses the captured carbon in the production of goods such as alcohols, biofuels, plastics or concrete.

Carbon-neutrality, also referred to as net-zero, is a state in which a country’s emissions are compensated by absorption and removal of greenhouse gases from the atmosphere. Absorption of the emissions can be increased by creating more carbon sinks such as forests, while removal of gases from the atmosphere requires futuristic technologies such as carbon capture and storage.

Interestingly, the Intergovernmental Panel on Climate Change (IPCC) has marked 2050 as the deadline by which the world must reach net zero if it wants to limit global warming to 1.5 degrees Celsius.

Geo-engineering refers to any large-scale attempt to alter the Earth’s natural climate system to counter the adverse impacts of global warming. Two broad geoengineering options are being explored: Solar Radiation Management (SRM) and Carbon Dioxide Removal (CDR) technologies.

Solar Radiation Management (SRM), in which materials are proposed to be deployed in Space to reflect incoming solar rays and prevent them from reaching Earth.

Then there are Carbon Dioxide Removal (CDR) technologies, which include Carbon Capture and Sequestration (CCS). While they offer quick-fix solutions for reducing emissions or temperatures, they are not particularly viable. The only method being tried out in practice is CCS.

Greenhouse gases (GHGs) are those gases in the Earth’s atmosphere that trap heat. They allow sunlight to pass through the atmosphere but prevent the heat that sunlight brings from returning into space. Essentially, GHGs act like a blanket that envelopes our planet and insulates Earth from the cold of space. This process of maintaining a warmer temperature is called the greenhouse effect.

The most notable GHGs are water vapour, carbon dioxide, methane, ozone, and nitrous oxide. These gases occur naturally and are a boon for the planet — in their absence, there wouldn’t be the greenhouse effect without which there wouldn’t be liquid water and any form of life.