Daily Quiz #83 UPSC Prelims Marathon – February 8, 2020

Explanation: Greenhouse gas, any gas that has the property of absorbing infrared radiation (net heat energy) emitted from Earth’s surface and reradiating it back to Earth’s surface, thus contributing to the greenhouse effect. Carbon dioxide, methane, and water vapour are the most important greenhouse gases. (To a lesser extent, surface-level ozone, nitrous oxides, and fluorinated gases also trap infrared radiation.) Greenhouse gases have a profound effect on the energy budget of the Earth system despite making up only a fraction of all atmospheric gases. Concentrations of greenhouse gases have varied substantially during Earth’s history, and these variations have driven substantial climate changes at a wide range of timescales. In general, greenhouse gas concentrations have been particularly high during warm periods and low during cold periods. These gases have a high capacity for absorbing infrared radiation or occur in significant quantities, whereas others have considerably lower capacities for absorption or occur only in trace amounts.

Explanation: Crocodiles are ambush hunters and apex predator of river systems of the India. There are three crocodilians species found in India, Mugger crocodile, the Gharial and the Saltwater Crocodile. Mugger crocodile and the gharial are found throughout the Indian subcontinent and they are ambush hunters, mostly prey on fish, reptiles, birds and mammals. Saltwater Crocodiles are the largest species of crocodilians family and largest of all living reptiles in the world. The apex predator found in saline and brackish mangrove swamp forest of Bhitarkanika and Sunderbans. Bhitarkanika National Park in Kendrapara district of Odisha is a separates swamp region and mangroves forest. The park is home to largest Saltwater Crocodiles in India and many other species of reptiles such as White Crocodile, Indian Python and King Cobra.

Explanation: The IMD is the national meteorological service of the country and it is the chief government agency dealing in everything related to meteorology, seismology and associated subjects. It was formed in 1875. The IMD is under the Ministry of Earth Sciences, Government of India.
•Cold Day: A cold-day condition is said to prevail when the maximum temperature during the day is at least 4.5°C below normal.
•Severe Cold Day: If the maximum temperature is at least 6.5°C below normal, it is classified as a severe cold day.
•Cold wave: Cold wave is characterized by a rapid and marked fall of temperature. The term ‘cold’ describes an unusual fall in temperature that is triggered by the transport of cold air masses into a specific area. The “wave” in cold wave is apparent in the upper-air flow (the jetstream), which is usually amplified into a strong ridge-trough pattern during a major cold outbreak. Cold waves affect much larger areas than blizzards, ice storms, and other winter hazards.

Explanation: Freshwater community consists of an array of organisms depending on the physico-chemical and biological characteristics of the freshwater environment.

Littoral zone: The littoral zone adjoins the shore (and is thus the home of rooted plants) and extends down to a point called the light compensation level, or the depth at which the rate of photosynthesis equals the rate of respiration. Within the littoral zone producers are of two main types: rooted or benthic plants, and phytoplankton (plant plankton) or floating green plants, which are mostly algae.

Limnetic Zone: The limnetic zone includes all the waters beyond the littoral zone and down to the light compensation level. The limnetic zone derives its oxygen content from the photosynthetic activity of phytoplankton and from the atmosphere immediately over the lake’s surface. The atmospheric source of oxygen becomes significant primarily when there is some surface disturbance of water caused by wind action or human activity. The community of the limnetic zone is composed only of plankton, nekton, and sometimes neuston (organisms resting or swimming on the surface).

Explanation: Bioremediation is the use of living micro organisms to degrade the environmental contaminants into less toxic forms. It uses naturally occurring bacteria and fungi or plants to degrade or detoxify substances hazardous to human health and/or the environment. The micro organisms may be indigenous to a contaminated area or they may be isolated from elsewhere and brought to the contaminated site. Contaminant compounds are transformed by living organisms through reactions that take place as a part of their metabolic processes. Biodegradation of a compound is often a result of the actions of multiple organisms. Bioremediation can be effective only where environmental conditions permit microbial growth and activity. The application often involves the manipulation of environmental parameters to allow microbial growth and degradation to proceed at a faster rate.