Environment Quiz: Environment Climate Change | November 25,2020

Methane (CH4) is emitted by natural sources such as wetlands, as well as human activities such as leakage from natural gas systems and the raising of livestock.
Smaller sources include termites, oceans, sediments, volcanoes, and wildfires.
Source: Shankar

Fluorinated gases are emitted through a variety of industrial processes such as aluminum and semiconductor manufacturing & Substitution for Ozone-Depleting Substances.
•Many fluorinated gases have very high global warming potentials (GWPs) relative to other greenhouse gases. Fluorinated gases are well-mixed in the atmosphere, spreading around the world after they’re emitted.
•Fluorinated gases are removed from the atmosphere only when they are destroyed by sunlight in the far upper atmosphere. In general, fluorinated gases are the most potent and longest lasting type of greenhouse gases emitted by human activities.
Source: Shankar

Black carbon (BC) is a solid particle or aerosol, (though not a gas) contributes to warming of the atmosphere.
•Black carbon, commonly known as soot, is a form of particulate air pollutant, produced from incomplete combustion.
•It consists of pure carbon in several linked forms. Black carbon stays in the atmosphere for only several days to weeks.
•Thus the effects of BC on the atmospheric warming and glacier retreat disappear within months of reducing emissions.
Source: Shankar

Oceans are an important reservoir for CO2, absorbing a significant quantity of it (one-third) produced by anthropogenic activities and effectively buffering climate change.
•Ocean acidification is the change in ocean chemistry – lowering of ocean pH (i.e. increase in concentration of hydrogen ions) driven by the uptake of carbon compounds by the ocean from the atmosphere.
•As the uptake of atmospheric carbon dioxide by the ocean increases, the concentration of hydrogen ions in the ocean increases, the concentration of carbonate ions decreases, the pH of the oceans decreases and the oceans become less alkaline – this process is known as ocean acidification.
Source: Shankar

Coastal waters are also affected by excess nutrient inputs, mostly nitrogen, from agriculture, fertilizers and sewage.
The resulting eutrophication leads to large plankton blooms, and when these blooms collapse and sink to the sea bed the subsequent respiration of bacteria decomposing the algae leads to a decrease in sea water oxygen and an increase in CO2 (a decline in pH).
Source: Shankar

UPWELLING: Surface Coastal regions periodically experience upwelling events where deeper ocean water circulates onto continental shelves and near-shore areas.
•This exposes the productive upper ocean ecosystems to colder water containing more nutrients & more CO2.
•As ocean acidification makes the upper oversaturated layer of sea water shallower each year, these natural upwelling events will more often cause under-saturated water to well up and flow to the shore.
•Coastal marine organisms that form shells are unaccustomed to such events, and periodic exposures to these significantly different conditions may affect these communities.
Source: Shankar

The VIMSAR, a major public healthcare center for western Odisha and parts of Chhattisgarh and Jharkhand, has many deaths cases of farmers, since September 2017.
•The reason behind these deaths is the consumption of Paraquat — a herbicide used in agricultural fields.
•Paraquat is a toxic chemical that is widely used as an herbicide (plant killer), primarily for weed and grass control.
Source: Indian Express

The European Investment Bank said that it would stop funding fossil fuel projects at the end of 2021, in a landmark decision.
•The ban on funding comes into effect a year later than originally proposed after lobbying by European Union member states.
•Under the new policy, energy projects applying for EIB funding will need to show they can produce one kilowatt hour of energy while emitting less than 250 grams of carbon dioxide, a move which bans traditional gas-burning power plants.
•Gas projects are still possible, but would have to be based on what the bank called “new technologies,” such as carbon capture and storage, combining heat and power generation or mixing in renewable gases with the fossil natural gas.
•The European Commission has only an observer role on the EIB board, but the powerful EU executive body has much sway and holds the power to cast a deciding vote at a deadlock between the bank’s current 28 shareholders, the EU member states.
•There was no need for that as the bank said that members representing 90% of its capital had approved the new energy lending policy.
•The EIB, the biggest multilateral lender in the world, has ambitious goals on sustainable finance.
Source: The Hindu

‘Green’ crackers have a small shell size compared to traditional crackers.
•They are produced using less harmful raw materials and have additives which reduce emissions by suppressing dust.
•Green crackers don’t contain banned chemicals such as lithium, arsenic, barium and lead.
•They are called Safe Water Releaser (SWAS), Safe Thermite Cracker (STAR) and Safe Minimal Aluminium (SAFAL) crackers.
Green crackers release water vapour and don’t allow the dust particles to rise. They are designed to have 30% less particulate matter pollution.
Source: The Hindu