Question

i) What is global warming ?​

Answer 1

Answer:

Global warming is the observed and projected increases in the average temperature of Earth's atmosphere and oceans.

Answer 2

Answer:

Global mean surface-temperature change from 1880 to 2018, relative to the 1951–1980 mean. The 1951–1980 mean is 14.19 °C (57.54 °F).[1] The black line is the global annual mean, and the red line is the five-year local regression line. The blue uncertainty bars show a 95% confidence interval.

Global warming is a long-term rise in the average temperature of the Earth's climate system, an aspect of climate change shown by temperature measurements and by multiple effects of the warming.[2][3] Though earlier geological periods also experienced episodes of warming,[4] the term commonly refers to the observed and continuing increase in average air and ocean temperatures since 1900 caused mainly by emissions of greenhouse gases in the modern industrial economy.[5] In the modern context the terms global warming and climate change are commonly used interchangeably,[6] but climate change includes both global warming and its effects, such as changes to precipitation and impacts that differ by region.[7][8] Many of the observed changes in climate since the 1950s are unprecedented in the instrumental temperature record, and in historical and paleoclimate proxy records of climate change over thousands to millions of years.[2]

In 2013, the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report concluded, "It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century."[9] The largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide. Climate model projections summarized in the report indicated that during the 21st century, the global surface temperature is likely to rise a further 0.3 to 1.7 °C (0.5 to 3.1 °F) to 2.6 to 4.8 °C (4.7 to 8.6 °F) depending on the rate of greenhouse gas emissions and on climate feedback effects.[10] These findings have been recognized by the national science academies of the major industrialized nations[11][a] and are not disputed by any scientific body of national or international standing