Climate Change and Global Warming: Notes for Exams

The correct answer is A, global warming. Carbon dioxide is a greenhouse gas: it lets in the short wave radiation of the sun but absorbs a part of the long wave infrared radiation that the warmed earth sends back, and radiates it downwards again. As its concentration rises with the burning of coal, oil and gas and with deforestation, more heat is held in the lower atmosphere and the average surface temperature of the earth rises. That rise is global warming, and it is the central driver of present day climate change.

Option B, air pressure, depends on temperature, altitude and the mass of air above a place, not on the share of a trace gas. Option C, conservation, is the protection and wise use of resources and is a human activity, not a consequence. Option D, rains, may change in pattern as the climate warms, but that is an indirect effect rather than the direct result asked for here.

The correct answer is B, the World Meteorological Organization and the United Nations Environment Programme. The two bodies set up the panel in 1988 so that governments would have a single authoritative summary of what science says about climate change. The panel does not carry out research or monitoring of its own; it reviews published scientific literature and publishes assessment reports and special reports, whose summaries for policymakers are approved line by line by member governments.

Option A names the education and agriculture agencies of the United Nations, which have no such role. Option C names financial institutions that fund climate projects but did not create the panel. Option D names the health and development agencies. The IPCC shared the Nobel Peace Prize in 2007 with Al Gore, a fact often asked alongside this one.

The correct answer is B, the Earth Summit at Rio de Janeiro in 1992. The United Nations Conference on Environment and Development, popularly called the Earth Summit, produced the Framework Convention on Climate Change along with the Convention on Biological Diversity and Agenda 21. The convention set the goal of stabilising greenhouse gas concentrations at a safe level and rests on the principle of common but differentiated responsibilities, which recognises that the industrial countries caused most of the accumulated emissions.

Option A, the Stockholm Conference of 1972, was the first world conference on the environment and led to the creation of the United Nations Environment Programme. Option C, the Johannesburg Summit, reviewed progress on sustainable development. Option D, the Copenhagen Conference, was a later meeting of the parties to this very convention.

The correct answer is C, 1997. The Kyoto Protocol was adopted at the third Conference of the Parties held in the Japanese city of Kyoto in 1997, and it came into force in 2005 after enough countries had ratified it. It was the first agreement to place legally binding limits on emissions, but only on the developed countries listed in Annex I of the convention, and it created three market mechanisms: emissions trading, joint implementation and the clean development mechanism, under which a project in a developing country could earn credits.

Option A, 1987, is the year of the Montreal Protocol on ozone depleting substances. Option B, 1992, is the year of the Rio Earth Summit and the framework convention itself. Option D, 2005, is the year the protocol entered into force, not the year it was adopted, and it is the commonest trap in this question.

The correct answer is A. The Paris Agreement, adopted at the twenty-first Conference of the Parties in 2015 and in force from November 2016, commits its parties to holding the increase in the global average temperature to well below two degrees Celsius above pre-industrial levels and to pursuing efforts to limit the increase to one and a half degrees. Unlike the Kyoto Protocol it covers all countries, and each decides its own nationally determined contribution, which it must report and revise over time.

Option B invents a figure and measures it from the present rather than from pre-industrial levels. Option C names a limit far above anything the agreement contemplates. Option D is wrong because the numerical goal is the best known feature of the agreement.

The correct answer is D, sulphur hexafluoride. Global warming potential measures how much heat a mass of a gas traps over a chosen period compared with the same mass of carbon dioxide, which is given the value one. Sulphur hexafluoride, used as an insulating gas in high voltage electrical switchgear, has by far the highest potential of the gases covered by the Kyoto basket, because it absorbs infrared radiation strongly and survives in the atmosphere for thousands of years.

Option A, carbon dioxide, is the reference gas with a potential of one; it matters most because of the sheer quantity released, not its strength. Option B, methane, traps much more heat than carbon dioxide over a century but breaks down in about a decade. Option C, nitrous oxide, is stronger still and also attacks stratospheric ozone, but neither comes close to sulphur hexafluoride.

The correct answer is C, eight. The National Action Plan on Climate Change was released in 2008 and is built around eight national missions: the National Solar Mission, the National Mission for Enhanced Energy Efficiency, the National Mission on Sustainable Habitat, the National Water Mission, the National Mission for Sustaining the Himalayan Ecosystem, the National Mission for a Green India, the National Mission for Sustainable Agriculture and the National Mission on Strategic Knowledge for Climate Change. Some address the cutting of emissions and others the task of adapting to a changed climate.

Options A, B and D give wrong counts. Candidates should be able to name at least the solar, water, Himalayan and green India missions, since questions often ask which of four given missions is not part of the plan.

The correct answer is A, depletion of the ozone layer. The Montreal Protocol was agreed in 1987 under the Vienna Convention to phase out the substances that destroy stratospheric ozone, chiefly chlorofluorocarbons used in refrigeration, air conditioning and aerosol sprays. It is regarded as the most successful environmental treaty because the phase-out actually happened and the ozone layer is expected to recover. Its Kigali Amendment of 2016 added hydrofluorocarbons, which do not harm ozone but are powerful greenhouse gases.

Option B belongs to the Ramsar Convention on wetlands. Option C belongs to CITES, the convention on international trade in endangered species. Option D belongs to the Basel Convention on the movement of hazardous waste across borders. These four conventions, with their subjects and their years, are worth learning as one table, because a question usually offers them as alternatives to one another.

The correct answer is B, Gurugram in India. The International Solar Alliance was launched jointly by India and France at the Paris climate conference in 2015 to promote solar energy among countries that lie largely between the tropics, and its secretariat was established at the campus of the National Institute of Solar Energy at Gwal Pahari in Gurugram, Haryana. It is the first treaty based international organisation to have its headquarters in India, which is the point examiners usually test.

Option A, Paris, is where the alliance was announced but not where it is based. Option C, Nairobi, hosts the United Nations Environment Programme. Option D, Abu Dhabi, hosts the International Renewable Energy Agency, which is a different body and a common distractor in this question.

The correct answer is D, increased ultraviolet radiation reaching the surface. That is the consequence of ozone depletion, a separate problem caused by chlorofluorocarbons thinning the ozone layer in the stratosphere, and it is addressed by the Montreal Protocol. Mixing the two problems is the single commonest error in this part of the syllabus.

Option A, the rise in sea level, follows both from the expansion of sea water as it warms and from the melting of land ice. Option B, the retreat of glaciers, is observed in the Himalaya, the Alps and the Andes and threatens the flow of rivers fed by them. Option C, coral bleaching, happens when unusually warm water makes corals expel the algae that live within them and give them colour, leaving them white and liable to die.