Environment MCQs 1

1. Which of the following gases has the highest global warming potential (GWP) over a 100-year period?

a) Carbon Dioxide (CO₂) b) Methane (CH₄) c) Nitrous Oxide (N₂O) d) Sulfur Hexafluoride (SF₆)

d) According to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6), 2021, sulfur hexafluoride (SF₆) has a global warming potential (GWP) of approximately 23,500 over a 100-year period. This means SF₆ is 23,500 times more effective at trapping heat in the atmosphere compared to CO₂, making it the gas with the highest GWP listed in the report.

2. Which of the following is a major cause of ocean acidification?

a) Plastic pollution b) Oil spills c) Carbon dioxide (CO₂) absorption d) Overfishing

c) The IPCC Fifth Assessment Report (AR5), 2014 states that ocean acidification is primarily caused by the absorption of carbon dioxide (CO₂) from the atmosphere. When CO₂ dissolves in seawater, it forms carbonic acid, which lowers the pH of the ocean and has significant effects on marine life, particularly organisms with calcium carbonate structures.

3. What percentage of the Earth's water is fresh water?

a) 1% b) 2.5% c) 10% d) 25%

b) As reported by the United Nations World Water Development Report (WWDR), 2021, only about 2.5% of the Earth's water is fresh water, which includes glaciers, ice caps, groundwater, and surface water like rivers and lakes. The rest, about 97.5%, is saltwater found in the oceans.

4. The concept of “Ecological Footprint” primarily measures:

a) The amount of renewable energy a country produces b) The environmental impact of human activities c) The number of endangered species in an area d) The biodiversity of an ecosystem

b) The Global Footprint Network, in its annual reports, defines the ecological footprint as a measure of how much land and water area a human population requires to produce the resources it consumes and to absorb its waste, including CO₂ emissions. It provides a way to assess human demand on natural ecosystems.

5. Which biome is characterized by the highest biodiversity?

a) Desert b) Tundra c) Tropical Rainforest d) Grassland

c) The United Nations Environment Programme (UNEP) and various ecological studies have consistently shown that tropical rainforests have the highest biodiversity among all biomes. This is due to their stable warm temperatures, high humidity, and constant availability of water and sunlight, which create ideal conditions for a vast number of species.

6. Which of the following is a primary driver of deforestation in the Amazon rainforest?

a) Mining b) Urbanization c) Cattle Ranching d) Logging for fuelwood

c) According to the Food and Agriculture Organization (FAO) State of the World’s Forests Report, 2020, cattle ranching is the leading cause of deforestation in the Amazon rainforest. Large tracts of forest are cleared to create pastures for cattle, driven by global demand for beef and other cattle products.

7. Which international agreement focuses specifically on the reduction of ozone-depleting substances?

a) Kyoto Protocol b) Paris Agreement c) Montreal Protocol d) Basel Convention

c) The Montreal Protocol on Substances that Deplete the Ozone Layer, 1987, is an international treaty designed to phase out the production and consumption of numerous substances that are responsible for ozone depletion. The protocol is widely recognized as one of the most successful environmental agreements to date.

8. Which invasive species is known for causing significant damage to aquatic ecosystems in North America?

a) Asian Carp b) Africanized Honey Bee c) Burmese Python d) Red Fox

a) The U.S. Geological Survey (USGS) has documented that Asian Carp, including species like the Bighead Carp and Silver Carp, have caused substantial ecological disruption in North American freshwater ecosystems, particularly in the Mississippi River basin. They outcompete native species for food and habitat, leading to declines in biodiversity.

9. What is the main purpose of the Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC)?

a) To eliminate all greenhouse gas emissions by 2050 b) To strengthen the global response to climate change by limiting global warming to well below 2 degrees Celsius above pre-industrial levels c) To promote renewable energy exclusively d) To ban the use of coal globally

b) The Paris Agreement, adopted at COP21 in 2015, aims to enhance the global response to climate change by keeping a global temperature rise this century well below 2 degrees Celsius above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degrees Celsius.

10. Which of the following is an example of a positive feedback mechanism in the context of climate change?

a) Increase in forest cover due to higher CO₂ levels b) Melting of polar ice reducing the Earth's albedo c) Decrease in ocean temperature due to CO₂ absorption d) Enhanced plant growth absorbing more CO₂

b) As outlined in the IPCC Sixth Assessment Report (AR6), 2021, melting polar ice is an example of a positive feedback mechanism. As ice melts, it reduces the Earth's albedo (reflectivity), causing more solar energy to be absorbed by the darker ocean or land, which leads to further warming and more ice melt, creating a self-reinforcing cycle.

If any answer found wrong, Please comment.

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