Causes and Effects of Climate Change | United Nations (2024)

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Climate Action

Fossil fuels – coal, oil and gas – are by farthe largest contributor to global climate change, accounting for over 75 per cent of global greenhouse gas emissions and nearly 90 per cent of all carbon dioxide emissions.

As greenhouse gas emissions blanket the Earth, they trap the sun’s heat. This leads to global warming and climate change. The world is now warming faster than at any point in recorded history. Warmer temperatures over time are changing weather patterns and disrupting the usual balance of nature. This poses many risks to human beings and all other forms of life on Earth.

Causes and Effects of Climate Change | United Nations (3)

Effects of Climate Change

Hotter temperatures

As greenhouse gas concentrations rise, so does the global surface temperature. The last decade, 2011-2020, is the warmest on record. Since the 1980s, each decade has been warmer than the previous one. Nearly all land areas are seeing more hot days and heat waves. Higher temperatures increase heat-related illnesses and make working outdoors more difficult. Wildfires start more easily and spread more rapidly when conditions are hotter. Temperatures in the Arctic have warmed at least twice as fast as the global average.

More severe storms

Destructive storms have become more intense and more frequent in many regions. As temperatures rise, more moisture evaporates, which exacerbates extreme rainfall and flooding, causing more destructive storms. The frequency and extent of tropical storms is also affected by the warming ocean. Cyclones, hurricanes, and typhoons feed on warm waters at the ocean surface. Such storms often destroy homes and communities, causing deaths and huge economic losses.

Increased drought

Climate change is changing water availability, making it scarcer in more regions. Global warming exacerbates water shortages in already water-stressed regions and is leading to an increased risk of agricultural droughts affecting crops, and ecological droughts increasing the vulnerability of ecosystems. Droughts can also stir destructive sand and dust storms that can move billions of tons of sand across continents. Deserts are expanding, reducing land for growing food. Many people now face the threat of not having enough water on a regular basis.

A warming, rising ocean

The ocean soaks up most of the heat from global warming. The rate at which the ocean is warming strongly increased over the past two decades, across all depths of the ocean. As the ocean warms, its volume increases since water expands as it gets warmer. Melting ice sheets also cause sea levels to rise, threatening coastal and island communities. In addition, the ocean absorbs carbon dioxide, keeping it from the atmosphere. But more carbon dioxide makes the ocean more acidic, which endangers marine life and coral reefs.

Loss of species

Climate change poses risks to the survival of species on land and in the ocean. These risks increase as temperatures climb. Exacerbated by climate change, the world is losing species at a rate 1,000 times greater than at any other time in recorded human history. One million species are at risk of becoming extinct within the next few decades. Forest fires, extreme weather, and invasive pests and diseases are among many threats related to climate change. Some species will be able to relocate and survive, but others will not.

Not enough food

Changes in the climate and increases in extreme weather events are among the reasons behind a global rise in hunger and poor nutrition. Fisheries, crops, and livestock may be destroyed or become less productive. With the ocean becoming more acidic, marine resources that feed billions of people are at risk. Changes in snow and ice cover in many Arctic regions have disrupted food supplies from herding, hunting, and fishing. Heat stress can diminish water and grasslands for grazing, causing declining crop yields and affecting livestock.

More health risks

Climate change is the single biggest health threat facing humanity. Climate impacts are already harming health, through air pollution, disease, extreme weather events, forced displacement, pressures on mental health, and increased hunger and poor nutrition in places where people cannot grow or find sufficient food. Every year, environmental factors take the lives of around 13 million people. Changing weather patterns are expanding diseases, and extreme weather events increase deaths and make it difficult for health care systems to keep up.

Poverty and displacement

Climate change increases the factors that put and keep people in poverty. Floods may sweep away urban slums, destroying homes and livelihoods. Heat can make it difficult to work in outdoor jobs. Water scarcity may affect crops. Over the past decade (2010–2019), weather-related events displaced an estimated 23.1 million people on average each year, leaving many more vulnerable to poverty. Most refugees come from countries that are most vulnerable and least ready to adapt to the impacts of climate change.

Based on various UN sources

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Causes and Effects of Climate Change | United Nations (2024)

FAQs

Causes and Effects of Climate Change | United Nations? ›

Human activities, such as burning fossil fuels and destroying rainforests, have an increasing influence on the climate and the Earth's temperature. This adds huge quantities of greenhouse gases to those naturally present in the atmosphere, increasing the greenhouse effect and global warming.

What are the causes and effects of climate change? ›

Human activities, such as burning fossil fuels and destroying rainforests, have an increasing influence on the climate and the Earth's temperature. This adds huge quantities of greenhouse gases to those naturally present in the atmosphere, increasing the greenhouse effect and global warming.

What has the UN said about climate change? ›

Climate Change is the defining issue of our time and we are at a defining moment. From shifting weather patterns that threaten food production, to rising sea levels that increase the risk of catastrophic flooding, the impacts of climate change are global in scope and unprecedented in scale.

What are the answers to climate change? ›

What are the solutions to climate change?
  • Keep fossil fuels in the ground. ...
  • Invest in renewable energy. ...
  • Switch to sustainable transport. ...
  • Help us keep our homes cosy. ...
  • Improve farming and encourage vegan diets. ...
  • Restore nature to absorb more carbon. ...
  • Protect forests like the Amazon. ...
  • Protect the oceans.

What are the 10 causes of climate change essay 500 words? ›

Causes of Global Warming
  • Greenhouse Gases. Large amounts of carbon dioxide are emitted by these power plants as a result of the combustion of fossil fuels for electricity generation. ...
  • Deforestation. ...
  • Burning of Fossil Fuels. ...
  • Transports and Vehicles. ...
  • Industrialization. ...
  • Waste Disposal.
Feb 27, 2024

What are the 5 effects of climate change essay? ›

The ocean level is rising, glaciers are melting, CO2 in the air is increasing, forest and wildlife are declining, and water life is also getting disturbed due to climatic changes.

What are the 3 main effects of climate change? ›

The potential future effects of global climate change include more frequent wildfires, longer periods of drought in some regions, and an increase in the wind intensity and rainfall from tropical cyclones.

What is the UN goal for climate change? ›

To limit global warming to 1.5°C, greenhouse gas emissions must peak before 2025 at the latest and decline 43% by 2030.

What is the UN Act now for climate change? ›

ActNow is the United Nations campaign for individual action on climate change and sustainability. Every one of us can help limit global warming and take care of our planet.

What are the UN promises for climate change? ›

The Climate Promise 2025 aims to accelerate efforts from local to international levels to take more ambitious steps to ensure the global temperature does not heat up beyond the 1.5° limit, a goal set with the 2015 Paris Agreement on climate change.

Can climate change be reversed? ›

While the effects of human activities on Earth's climate to date are irreversible on the timescale of humans alive today, every little bit of avoided future temperature increases results in less warming that would otherwise persist for essentially forever.

What are the two main responses to climate change? ›

Because we are already committed to some level of climate change, responding to climate change involves a two-pronged approach: Reducing emissions of and stabilizing the levels of heat-trapping greenhouse gases in the atmosphere (“mitigation”); Adapting to the climate change already in the pipeline (“adaptation”).

What is the UN definition of climate change? ›

"Climate change" means a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods.

What is the biggest contributor to climate change? ›

The largest source of greenhouse gas emissions from human activities in the United States is from burning fossil fuels for electricity, heat, and transportation.

How bad will climate change get? ›

By 2100, the average U.S. temperature is projected to increase by about 3°F to 12°F, depending on emissions scenario and climate model. An increase in average temperatures worldwide implies more frequent and intense extreme heat events, or heat waves.

What are 9 effects of climate change? ›

Climate change may aggravate erosion, decline in organic matter, salinisation, soil biodiversity loss, landslides, desertification and flooding. The effect of climate change on soil carbon storage can be related to changing atmospheric CO2 concentrations, increased temperatures and changing precipitation patterns.

What are the major events caused by climate change? ›

More Severe and Prolonged Heat Waves

In California's Death Valley, which is known to be one of the hottest places on the planet, recorded a temperature of 54.4C on July 9, the highest record in the world since at least the 1930s. The desert valley went on to had its hottest summer on record.

How does climate change affect humans? ›

Climate change increases the risk of illness through increasing temperature, more frequent heavy rains and runoff, and the effects of storms. Health impacts may include gastrointestinal illness like diarrhea, effects on the body's nervous and respiratory systems, or liver and kidney damage.

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