Overview of the “Temperature Change by Location - Map” in En-ROADS. Watch the video below for a summary.
Big Messages:
Local temperature increase on land is almost always greater than the average global temperature increase (shown at the top of the map).
By contrast, the local temperature increase over the oceans is typically less than the global average. This is because the ocean surface, which covers approximately 70% of Earth, has a larger heat capacity and is able to move heat from the surface to lower ocean layers and to the air through evaporation. Learn more about this dynamic here.
Local temperature increase is also typically larger near the North and South Poles and smaller near the equator. This polar amplification results from several factors, including the loss of reflective ice and snow, increased absorption of sunlight by darker ocean surfaces, and changes in cloud cover, water vapor, and heat transport. Learn more about polar amplification here.
As local temperature change is directly related to global temperature change, strong climate policies that rapidly reduce greenhouse gas emissions today are important to limit local warming.
Adaptation measures will be especially important in areas where local temperature increases are more pronounced, because these regions often face changes beyond what their infrastructure was designed to handle.
Facilitator Tips:
Click on or search for a location to see projected temperature change relative to 1850 levels in the selected year for your scenario.
Compare the Baseline Scenario in a recent year (e.g., 2020) with a future year (e.g., 2100) to show the increase in temperature for that location. After creating a scenario with climate action, compare the Baseline and Current Scenario for the future year to highlight the impact of reducing emissions and the need for adaptation.
To explore some of the repercussions of long-term temperature change, pair this map with heat-related data such as “Deaths from Extreme Heat,” “Extreme Heat Days—Map,” and “Extreme Humidity and Heat Days—Map.”
Equity Considerations:
Warming of the Arctic threatens the ways of life of Indigenous peoples and local communities who rely on stable ice and snow for livelihoods, transportation, food security, and cultural continuity.
Because land areas heat faster than oceans, populations living inland may face higher exposure to extreme heat.
Although local temperature increases near the equator may appear smaller, these regions are already warm. Small increases can push heat and humidity beyond human tolerance, especially in cities lacking widespread air conditioning and cooling infrastructure. Labor-intensive work, outdoor activities, and agricultural livelihoods are especially affected.
Technical Clarifications:
The map is provided by Bringing Computation to the Climate Challenge (BC3), a project of the MIT Climate Grand Challenges program. Learn more about BC3 at bc3.mit.edu.
The map is produced by a general circulation model (GCM) emulator trained on CMIP6 Earth system models.
The emulator utilizes a pattern scaling technique that outputs geospatial temperature projections based on the global temperature change of the scenario in a given year.
The map is divided into squares that are 1.5° longitude by 1.5° latitude. The squares vary in area depending on latitude. Near the equator, a square is approximately 27,722 square kilometers (10,704 square miles). At mid-latitudes (i.e., 45°N or 45°S), a square is approximately 19,678 square kilometers (7,598 square miles). The area of a square approaches zero as you near the poles.
Frequently Asked Questions:
Why is there less warming in India and Southeast Asia than the global average? One factor is high levels of air pollution in the region. Tiny particles in the air reflect sunlight back to space and brighten clouds, reducing how much solar energy reaches the surface. Scientists are still working to understand this phenomenon, and several factors likely contribute.
Why is there an area in the North Atlantic with less warming? This yellow “cold blob” south of Greenland is probably connected to changes in winds and an influx of freshwater from melting ice. Earlier studies suggested it was caused by a slowdown of the Atlantic Meridional Overturning Circulation (AMOC), but more recent research has not confirmed that link.
Why is the land at the tip of South America warming less than land in the Arctic? The region near the southern tip of South America is mostly ocean rather than land, and oceans heat up more slowly than land does. In addition, the Southern Ocean is warming less than the Arctic Ocean.
Why is the Arctic Ocean warming more than the Southern Ocean? The Arctic Ocean is warming more rapidly than the Southern Ocean due to several factors:
Albedo effect: Arctic sea ice is melting, exposing darker ocean water that absorbs more sunlight, accelerating warming. In contrast, Antarctica’s landmass remains mostly covered by reflective snow and ice, which bounces sunlight back into space.
Geography and land distribution: The Arctic is mostly ocean surrounded by land, while the Southern Ocean surrounds the Antarctic continent. This difference affects heat absorption and circulation patterns.
Ocean mixing: The Southern Ocean has strong mixing between ocean layers and upwelling of cold deep water, which spreads heat deeper and slows surface warming. In the Arctic, ocean layers mix less, so heat remains near the surface, amplifying warming.
Melting ice reduces ocean warming: Fresh meltwater from Antarctic ice sheets reduces warming of the surface ocean.
Why do dry inland areas warm more than other areas? Dry interior regions, such as the Arabian Peninsula, lack moisture for evapotranspiration, a natural cooling process where water evaporates from soil and vegetation and carries heat away. Without this cooling mechanism, temperatures rise more quickly.
Why is the temperature increase over most land areas higher than the global average? The global average temperature increase takes into account both land and ocean warming. Temperature increases over land are almost always greater than the global average. In contrast, warming over the oceans is usually lower than the global average. This is because the ocean surface, which covers approximately 70% of Earth, has a larger heat capacity and is able to move heat from the surface to lower ocean layers and to the air through evaporation.