NCERT notes on important topics for the competitive examination aspirants. These notes will also be beneficial for competitive exams like IAS, banking PO, SSC, state civil services exams, and so on. Further, this article talks about Climate Change.

What is Weather?

Both climate and weather are different from each other. Weather is a day-to-day condition of the atmosphere at any place concerning temperature, pressure, wind, humidity, and rainfall.

What is Climate?

The term climate is the average weather in a given area throughout a longer period. The word climate describes information on, e.g., the average temperature in different seasons, rainfall, and sunshine.

Types of climates are as follows:

• Tropical climate
• Desert/dry climate
• Temperate climate
• Polar climate
• Mediterranean climate

What are the Rapid Changes of Climate?

Following are the pieces of evidence of rapid climate change:

1. Global Temperature Rise: Earth’s normal surface temperature has risen about 2.05 degrees Fahrenheit (1.14 degrees Celsius) since the late nineteenth century, a change driven generally by expanded carbon dioxide and other human-made outflows into the atmosphere.
2. Warming Ocean: The ocean has absorbed quite a bit of this expanded warmth, with the top 100 meters (around 328 feet) of the ocean showing warming of more than 0.6 degrees Fahrenheit (0.33 degrees Celsius) since 1969. Earth stores 90% of the additional energy in the ocean.
3. Shrinking Ice Sheets: The Antarctic and Greenland ice sheets have diminished in mass. This information is from NASA's Gravity Recovery and Climate Experiment showing Greenland lost a normal of 279 billion tons of ice for each year somewhere in the range of 1993 and 2019, while Antarctica lost around 148 billion tons of ice for every year.

4. Glacial Retreat: Glaciers are retreating all around the globe — including the Alps, Himalayas, Andes, Rockies, Alaska, and Africa.
5. Decreased Snow Cover: Satellite observations reveal that the measure of spring snow cover in the Northern Hemisphere has decreased in the course of recent many years and the snow is melting earlier.
6. Sea Level Rise: Worldwide ocean level rose around 8 inches (20 centimeters) in the only remaining century. The rate over the most recent twenty years, however, is almost doubled that of the only remaining century and accelerating slightly every year
7. Declining Arctic Sea Ice: Both the extent and thickness of Arctic ocean ice has declined quickly throughout the last several decades.
8. Extreme Events: The number of records high-temperature occasions in the United States has been expanding, while the number of record low-temperature occasions has been diminishing, since 1950. The U.S. has additionally seen expanding the number of intense rainfall events.
9. Ocean Acidification: Since the start of the Industrial Revolution, the acidity of surface ocean waters has expanded by about 30%. This expansion is the consequence of people producing more carbon dioxide into the environment and hence more being absorbed into the ocean. The ocean has absorbed somewhere in the range of 20% and 30% of complete anthropogenic carbon dioxide emanations in late many years (7.2 to 10.8 billion metric tons for every year).

What are the Natural Causes of Climate Change?

There are various regular components that are responsible for climate change. A portion of the more prominent ones is continental drift, volcanoes, ocean currents, the earth's tilt, and comets and meteorites. How about we take a look at them in a little detail:

1. Continental drift You may have seen something curious about South America and Africa on a guide of the world - don't they appear to find a way into one another like pieces in a jigsaw puzzle? Around 200 million years prior they were consolidated! Researchers accept that in those days, the earth was not as we see it today, but rather the continents were all essential for one large landmass.
2. Volcanoes At the point when a volcano erupts, it throws out large volumes of sulfur dioxide (SO2), water vapor, dust, and ash into the atmosphere. Despite the fact that the volcanic activity may last a couple of days, yet the large volumes of gases and ash can impact climatic patterns for quite a long period.
3. The earth's tilt The Earth's orbit is fairly elliptical, which implies that the distance between the earth and the Sun differs throughout a year. We for the most part consider the earth's axis as being fixed, all things considered, it generally appears to highlight Polaris (otherwise called the Pole Star and the North Star).
4. Ocean currents The oceans are a significant segment of the climate system. They cover about 71% of the Earth and absorb about twice as much of the sun's radiation as the atmosphere or the land surface.

5. Astronomical causes The astronomical elements are the fluctuations in the solar output related to sunspot activities. Sunspots are shaded and cooler patches on the sun that ascend and descend in a recurring pattern, when the number of sunspots progress, cooler and wetter weather and more prominent storminess occur. All these modify the amount of insolation obtained from the sun, which in turn, might have a bearing on the climate.

What are the Human Causes of Climate Change?

Greenhouse Gases and Their Sources

1. Burning fossil fuels: Fossil fuels, for example, oil, gas, and coal contain carbon dioxide that has been ‘locked away' in the ground for thousands of years. At the point when we remove these from the land and consume them, we discharge the put-away carbon dioxide into the air.
2. Deforestation: Forests eliminate and store carbon dioxide from the atmosphere. Cutting them down implies that carbon dioxide develops faster since there are no trees to absorb it. Not just that, trees discharge the carbon they put away when we burn them.
3. Agriculture: Planting crops and rearing animals discharges a wide range of greenhouse gases into the air. For instance, animals produce methane, which is 30 times more powerful than carbon dioxide.

Concentration of Greenhouse Gases

• The principal Greenhouse gases of attention are Methane (CH4), Chlorofluorocarbons (CFCs), Nitrous oxide (N2O), Carbon dioxide (CO2), including Ozone (O3).
• Several other gases such as Nitric oxide (NO) and Carbon monoxide (CO) readily react with Greenhouse gases and affect their density in the atmosphere.
• The most comprehensive concentration of Greenhouse gas in the atmosphere is carbon dioxide.

Global warming

• The term global warming refers to the gradual increase in the earth’s surface temperature.
• Human activities such as combusting fossil fuels, farming, and land clearing are doubling the estimate of greenhouse gases discharged into the atmosphere.
• This is deceiving extra heat, and causing the temperature of the earth to rise and eventually result in Global Warming.

FAQs

Question: What is the difference between weather and climate?

Question: How do weather and climate affect human activities?

Question: What is climate change?

Question: What are the main factors that influence climate?

Question: How has human activity contributed to climate change?

MCQs

1. What is the primary difference between weather and climate?

A) Weather refers to short-term conditions; climate refers to long-term average conditions.

B) Weather affects daily activities; climate does not.

C) Weather is influenced by human activities; climate is not.

D) Weather and climate are the same.

2. Which of the following is a major contributor to climate change?

A) Ocean currents

B) Human emissions of greenhouse gases

C) Solar radiation

D) Volcanoes

3. Which of the following is NOT a factor that influences climate?

A) Latitude

B) Wind patterns

C) Moon phases

D) Ocean currents

4. What is a primary cause of global warming?

A) Increased solar radiation

B) Human emissions of carbon dioxide

C) Increased volcanic activity

D) The Earth’s changing orbit

5. Which of the following is an example of climate, not weather?

A) A rainy day in July

B) Average temperature in July for the past 30 years

C) A sudden thunderstorm

D) A snowstorm in December

GS Mains Questions and Model Answers

Q1: Explain the factors that influence the climate of a region.

Answer: The climate of a region is influenced by several factors:

• Latitude: Regions closer to the equator are warmer due to the direct rays of the sun, whereas areas near the poles are cooler due to the sun’s rays being spread over a larger area.
• Altitude: Higher altitudes generally experience cooler temperatures, as temperature decreases with elevation.
• Distance from the sea: Coastal areas have milder climates because the sea moderates temperatures, while inland areas experience more extreme temperature variations.
• Wind patterns: Winds help distribute heat and moisture around the Earth, affecting temperature and rainfall patterns.
• Ocean currents: Warm ocean currents can raise temperatures in coastal regions, while cold currents can cool them down.
• Topography: Mountains can block the movement of air masses, creating rain shadows, where one side of the mountain range is dry, while the other is wet.

These factors collectively determine the climate of a region, affecting agriculture, human settlement, and lifestyle.

Q2: What are the causes of climate change and its impact on the environment?

Answer: The primary cause of climate change is the increased concentration of greenhouse gases in the atmosphere due to human activities, such as the burning of fossil fuels, deforestation, and industrial emissions. These activities release carbon dioxide, methane, and nitrous oxide, trapping heat in the atmosphere and leading to global warming. Climate change also results from natural processes, such as volcanic activity and variations in solar radiation, but human activities have accelerated these changes significantly.

The impact of climate change on the environment includes rising global temperatures, melting glaciers and polar ice caps, rising sea levels, and changing weather patterns. This leads to more frequent and severe weather events like storms, floods, and droughts. Biodiversity is threatened as ecosystems and species struggle to adapt to the changing climate. Agriculture and water resources are also at risk, which can lead to food insecurity and economic instability, particularly in vulnerable regions.

Q3: How does climate change affect weather patterns and human life?

Answer: Climate change has a profound effect on weather patterns, leading to extreme weather events such as heatwaves, heavy rainfall, floods, and droughts. Rising global temperatures cause shifts in weather systems, resulting in more frequent and intense storms, altered precipitation patterns, and changing wind directions. This disrupts the natural rhythms of ecosystems, agriculture, and human settlements.

Human life is significantly impacted by these changes. Agriculture faces challenges due to altered growing seasons, water scarcity, and unpredictable weather, affecting food production and livelihoods. Increased heatwaves can lead to health risks, especially for vulnerable populations. Additionally, rising sea levels threaten coastal cities, while flooding can cause infrastructure damage and displacement of communities. Extreme weather also strains healthcare systems, as the frequency of diseases like malaria, dengue, and waterborne diseases increases. As the global climate continues to change, adaptation strategies are crucial for mitigating its effects on both the environment and human life.

Previous Year Questions on  Weather Climate and Its Changes

1. UPSC CSE 2020

Question: Discuss the impact of climate change on agriculture and water resources.

Answer: Climate change significantly impacts agriculture by altering growing seasons, reducing water availability, and causing extreme weather events. Rising temperatures and erratic rainfall patterns affect crop yields, while increased droughts reduce water resources for irrigation. This threatens food security and the livelihood of farmers.

2. UPSC CSE 2019

Question: Explain the role of human activities in contributing to climate change.

Answer: Human activities such as the burning of fossil fuels, deforestation, and industrial emissions have increased the concentration of greenhouse gases in the atmosphere. These gases trap heat, leading to global warming, altered weather patterns, and climate change. These activities are the primary drivers of current climate shifts.