Global Warming: Impact on the Global Climate

The gradual rise in earth’s temperature known as global warming is typically brought on by the greenhouse effect, which is brought on by elevated amounts of carbon dioxide, CFCs, and other pollutants. It has an immense impact on the global climate as well. Read here to know more about it.

Global warming is the long-term heating of the Earth’s surface observed since the pre-industrial period (between 1850 and 1900) due to human activities.

The leading cause was primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere.

This term is not interchangeable with the term “climate change.”

Human activities are thought to have contributed to an increase in Earth’s average global temperature of about 1 degree Celsius (1.8 degrees Fahrenheit) since the pre-industrial era.

This temperature increase is currently happening at a rate of more than 0.2 degrees Celsius (0.36 degrees Fahrenheit) per decade.

Human activity since the 1950s has contributed to the current warming trend, which has been accelerating at an unheard-of rate for millennia.

(Weather vs Climate:

• Weather refers to atmospheric conditions that occur locally over short periods, from minutes to hours or days. Familiar examples include rain, snow, clouds, winds, floods, or thunderstorms.
• Climate, on the other hand, refers to the long-term (usually at least 30 years) regional or even a global average of temperature, humidity, and rainfall patterns over seasons, years, or decades.)

Global warming vs Climate change

Although these expressions are occasionally used interchangeably, they are not the same.

• Changes in global weather patterns and growing seasons are referred to as climate change. It also refers to the rise in sea level brought on by melting ice sheets and glaciers and the expansion of warmer oceans.
• Climate change brought on by global warming poses a severe threat to life on earth in the form of catastrophic weather events and extensive flooding.

Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates. These changes have a broad range of observed effects that are synonymous with the term.

Human activities, especially the burning of fossil fuels, which raises the concentrations of heat-trapping greenhouse gases in Earth’s atmosphere and thus increases the planet’s average surface temperature, are to blame for the climate changes that have been observed since the middle of the 20th century.

In addition to internal variability (such as cyclical ocean patterns like El Nino, La Nina, and the Pacific Decadal Oscillation) and external forcings (such as volcanic activity, changes in the Sun’s energy output, and variations in Earth’s orbit), natural processes that have been outweighed by human activities can also contribute to climate change.

Key indicators of climate change are:

• global land and ocean temperature increases
• rising sea levels
• ice loss at Earth’s poles and in mountain glaciers
• frequency and severity changes in extreme weather such as hurricanes, heatwaves, wildfires, droughts, floods, and precipitation
• cloud and vegetation cover changes

The gradual increase in the planet’s surface temperature is known as global warming.

Although this warming trend has been around for a while, the burning of fossil fuels has greatly accelerated its pace over the past century. The amount of fossil fuels burned has increased along with the size of the human population.

Burning fossil fuels such as coal, oil, and natural gas results in the “greenhouse effect,” which affects the atmosphere of Earth.

• The greenhouse effect is when the Sun’s rays penetrate the atmosphere, but when that heat is reflected off the surface cannot escape back into space.
• Gases produced by the burning of fossil fuels prevent the heat from leaving the atmosphere.
• These greenhouse gasses are carbon dioxide, chlorofluorocarbons, water vapor, methane, and nitrous oxide.
• The excess heat in the atmosphere has caused the average global temperature to rise over time, otherwise known as global warming.

Global warming is one of the causes of climate change.

Also read: State of Global Climate Report 2023

Impact of global warming on global climate

Scientists agree that the earth’s rising temperatures are fueling longer and hotter heat waves, more frequent droughts, heavier rainfall, and more powerful hurricanes.

The impacts of global warming are being felt everywhere.

• Extreme heat waves have caused tens of thousands of deaths around the world in recent years.
• Antarctica has lost nearly four trillion metric tons of ice since the 1990s.
• It is causing the permafrost to thaw in the Arctic region.

The rate of loss could speed up if we keep burning fossil fuels at our current pace, some experts say, causing sea levels to rise several meters in the next 50 to 150 years and wreaking havoc on coastal communities worldwide.

The earth’s ocean temperatures are getting warmer, so tropical storms can pick up more energy.

In other words, global warming can turn a category 3 storm into a more dangerous category 4 storm.

• Scientists have found that the frequency of North Atlantic hurricanes has increased since the early 1980s, as has the number of storms that reach categories 4 and 5.

The impact of global warming is also seen in but not limited to:

• The risk of wildfires will continue to rise as a result of melting glaciers, early snowmelt, and severe droughts.
• Increased coastal flooding will be caused by rising sea levels throughout the coastal regions.
• Cities, farms, and forests will see more bothersome pests, heat waves, torrential downpours, and flooding. Agriculture and fisheries may be harmed or destroyed by all of these.
• Many plant and animal species may go extinct if environments like coral reefs and alpine meadows are damaged.
• Because pollen-producing ragweed is growing more quickly, there is more air pollution, and more people are exposed to these conditions, allergies, asthma attacks, and infectious disease outbreaks will become more frequent.

Even though everyone is impacted by climate change, not everyone is equally impacted. Typically, those who are indigenous, persons of color, or economically marginalized are severely harmed. Even though these same groups have made the least effort to contribute to climate change, they are more exposed to its severe effects due to inequities embedded into our housing, healthcare, and labor systems. This is known as environmental racism.

Also read: Planetary Boundaries

Global warming contributions by countries

In recent years, China has taken the lead in global-warming pollution, producing about 26 percent of all CO₂ emissions.

The United States comes in second. Despite making up just 4 percent of the world’s population, the nation produces about 13 percent of all global CO₂ emissions which is nearly as much as the European Union and India (third and fourth place) combined.

And America is still number one, by far, in cumulative emissions over the past 150 years. As a top contributor to global warming, the United States must help propel the world to a cleaner, safer, and more equitable future.

Global climate data

• Global temperatures rose about 1.8°F (1°C) from 1901 to 2020.
• Sea level rise has accelerated from 1.7 mm/year throughout most of the twentieth century to 3.2 mm/year since 1993.
• Glaciers are shrinking: the average thickness of 30 well-studied glaciers has decreased by more than 60 feet since 1980.
• The area covered by sea ice in the Arctic at the end of summer has shrunk by about 40% since 1979.
• The amount of carbon dioxide in the atmosphere has risen by 25% since 1958, and by about 40% since the Industrial Revolution.
• Snow is melting earlier compared to long-term averages.

Way forward

Levels of the two most important anthropogenic greenhouse gases, carbon dioxide, and methane, continued their unrelenting rise in 2020 despite the economic slowdown caused by the coronavirus pandemic response.

Moving away from fossil fuels is the first step in preventing climate change. Renewable energy sources including solar, wind, biomass, and geothermal need to be highlighted.

Producing clean energy is crucial, but it’s as necessary to use more cost-effective technologies to reduce our energy and water usage, such as LED lightbulbs and cutting-edge shower systems.

Promoting carpooling, public transportation, and electric and hydrogen mobility are all effective ways to cut CO2 emissions and combat global warming.

Both the construction of new low-energy buildings and the renovation of existing structures are required to reduce the CO2 emissions from buildings, which are brought on by heating, cooling, hot water, and lighting.

It should also be a primary goal to promote more efficient use of natural resources, halt widespread deforestation, and improve the sustainability and productivity of agriculture.

Developing responsible consumption habits is essential, whether it’s for food (especially meat), apparel, cosmetics, or cleaning supplies. Last but not least, recycling is a crucial component of waste management.

Previous year question

Q. Discuss global warming and mention its effects on global climate. Explain the control measures to bring down the level of greenhouse gases that cause global warming, in the light of the Kyoto Protocol, 1997. (Answer in 250 words) 15 marks (GS Paper 3, 2022)

Read: 

• Climate Resilient Health Systems;
• Impact of climate change on Indian monsoon;
• Climate Change Impact on Earth’s Rotation

-Article written by Swathi Satish