How Can We Help?
You are here:
< Back

The Climate Change Portal

Surface air temperature change over the past 50 years.[1]

In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is primarily caused by humans burning fossil fuels since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices add to greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary greenhouse gas driving global warming, has grown by about 50% and is at levels unseen for millions of years.

Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimise future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise.

Climate change threatens people with increased flooding, extreme heat, increased food and water scarcity, more disease, and economic loss. Human migration and conflict can also be a result. The World Health Organization (WHO) calls climate change the greatest threat to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming. Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for a small share of global emissions, yet have the least ability to adapt and are most vulnerable to climate change.

Many climate change impacts have been felt in recent years, with 2023 the warmest on record at +1.48 °C (2.66 °F) since regular tracking began in 1850. Additional warming will increase these impacts and can trigger tipping points, such as melting all of the Greenland ice sheet. Under the 2015 Paris Agreement, nations collectively agreed to keep warming "well under 2 °C". However, with pledges made under the Agreement, global warming would still reach about 2.7 °C (4.9 °F) by the end of the century. Limiting warming to 1.5 °C would require halving emissions by 2030 and achieving net-zero emissions by 2050.

Fossil fuel use can be phased out by conserving energy and switching to energy sources that do not produce significant carbon pollution. These energy sources include wind, solar, hydro, and nuclear power. Cleanly generated electricity can replace fossil fuels for powering transportation, heating buildings, and running industrial processes. Carbon can also be removed from the atmosphere, for instance by increasing forest cover and farming with methods that capture carbon in soil. (Full article...)

Selected article – show another

Climate change mitigation (or decarbonisation) is action to limit the greenhouse gases in the atmosphere that cause climate change. Current climate change mitigation policies are insufficient as they would still result in global warming of about 2.7 °C by 2100, significantly above the 2015 Paris Agreement's goal of limiting global warming to below 2 °C. Climate change mitigation actions include conserving energy and replacing fossil fuels with clean energy sources. Secondary mitigation strategies include changes to land use and removing carbon dioxide (CO2) from the atmosphere. Costs of climate change mitigation are estimated at around 1% and 2% of GDP.

Lower cost climate change mitigation include solar energy and wind power. The availability of sunshine and wind is variable and can require electrical grid upgrades, such as using long-distance electricity transmission to group a range of power sources. Energy storage can also be used to even out power output, and demand management can limit power use when power generation is low. Cleanly generated electricity can usually replace fossil fuels for powering transportation, heating buildings, and running industrial processes. Certain processes are more difficult to decarbonise, such as air travel and cement production. Carbon capture and storage (CCS) can be an option to reduce net emissions in these circumstances, although fossil fuel power plants with CCS technology is currently a high cost climate change mitigation strategy.

Human land use changes such as agriculture and deforestation cause about 1/4th of climate change. These changes impact how much CO2 is absorbed by plant matter and how much organic matter decays or burns to release CO2. These changes are part of the fast carbon cycle, whereas fossil fuels release CO2 that was buried underground as part of the slow carbon cycle. Methane is a short lived greenhouse gas that is produced by decaying organic matter and livestock, as well as fossil fuel extraction. Land use changes can also impact precipitation patterns and the reflectivity of the surface of the Earth. It is possible to cut emissions from agriculture by reducing food waste, switching to a more plant-based diet (also referred to as low-carbon diet), and by improving farming processes. (Full article...)
List of selected articles

Selected picture – show another

Credit: NASA
The collapse of Larsen B Ice Shelf, showing the diminishing extent of the shelf from 1998 to 2002

WikiProjects

In the news

Selected biography – show another

Elizabeth Wathuti in 2022

Elizabeth Wanjiru Wathuti (born August 1, 1995) is a Kenyan environment and climate activist and founder of the Green Generation Initiative, which nurtures young people to love nature and be environmentally conscious at a young age and has now planted 30,000 tree seedlings in Kenya.

In 2019, she was awarded the Africa Green Person of the Year Award by the Eleven Eleven Twelve Foundation and named as one of the 100 Most Influential Young Africans by the Africa Youth Awards. (Full article...)

General images

The following are images from various climate-related articles on Wikipedia.

Did you know – show another

... that global warming is cited as the main reason why southern England is becoming suitable for wine production and that it has similar soils and latitude to the Champagne region of France?

(Pictured left: A vineyard in Wyken, a suburb of Coventry, England)

Other "Did you know" facts... Read more...

Related portals

Selected panorama – show another

Sea level trends between 1993 and 2010. Per the U.S. National Oceanic and Atmospheric Administration (NOAA), "The following maps provide estimates of sea level rise based on measurements from satellite radar altimeters. The local trends were estimated using data from TOPEX/Poseidon (T/P), Jason-1, and Jason-2, which have monitored the same ground track since 1992. An inverted barometer has been applied. The estimates of sea level rise do not include glacial isostatic adjustment effects on the geoid, which are modeled to be +0.2 to +0.5 mm/year when globally averaged."

Topics


Categories

Web resources


Things to do

Wikimedia

References

  1. ^ "GISS Surface Temperature Analysis (v4)". NASA. Retrieved 12 January 2024.
  2. ^ Bhargav, Vishal (2021-10-11). "Climate Change Is Making India's Monsoon More Erratic". www.indiaspend.com. Retrieved 2021-10-11.
  3. ^ Tiwari, Dr Pushp Raj; Conversation, The. "Nobel prize: Why climate modellers deserved the physics award – they've been proved right again and again". phys.org. Retrieved 2021-10-11.
Discover Wikipedia using portals

Purge server cache

Categories
Table of Contents