After 2C: Glossary

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35 entries

Atlantic Meridional Overturning Circulation (AMOC): a massive system of currents that transports warm surface waters northward from the tropics and sends cold, deep water south.
Artificial Intelligence: computing systems capable of performing tasks that previously required human brains. The advanced AI systems in the timelines are Large Language Models (LLMs), which perform seemingly superhuman cognitive tasks by recognizing patterns by passing realms of data through layers of interconnected calculations.
Breadbaskets: agriculturally productive regions that supply food, predominantly grains, to much of the world.
Climate Adaptation: adjusting to ongoing or expected climate changes to reduce damage or exploit new opportunities.
Climate Change: a shift in average weather and weather variance – sometimes conceived as the “weather you can expect” versus the “weather you can get” – in a particular region, or globally, that lasts at least 30 years.
Climate Mitigation: lowering greenhouse gas emissions to reduce global warming.
Climate Models: a computer simulation of Earth’s climate, based on the known physics of the climate system.
Climate System: the interacting parts of the Earth, from the oceans to the atmosphere, from the biosphere to the lithosphere, that shape the planet’s climate.
Decarbonization: the systematic elimination of carbon dioxide and other greenhouse gas emissions from an economy, industry, or energy system, typically through transitioning away from fossil fuels.
Direct Air Capture (DAC): technology that pulls carbon dioxide out of ambient air and stores it, underground or elsewhere, as a way to lower emissions.
El Niño: a recurring warming of the central and eastern tropical Pacific Ocean that lasts many months and often peaks near the end of the year. It develops when changes in atmospheric pressure weaken the trade winds, allowing warm surface water to spread eastward. Conversely, during a La Niña, the trade winds strengthen, pushing warm water into the tropics of the western Pacific and allowing deeper, colder water to reach the surface of the eastern Pacific. El Niño and La Niña alter the temperature of so much water that they alter weather all over the world.
Epidemic: a disease outbreak spreads quickly and affects far more people than normally expected in a particular population or region. An epidemic that spreads across many countries is called a pandemic.
Geoengineering: deliberate, large-scale interventions in Earth's climate system that could slow down, halt, or even reverse global warming.
Green economy: an economic model that promotes sustainable growth while reducing environmental damage, emissions, and resource depletion.
Greenhouse Gas (GHG): a gas, such as carbon dioxide or methane, that warms Earth by absorbing and re-emitting heat radiated from its surface.
Greenland Ice Sheet: the world's second largest body of ice, covering around 80% of Greenland.
Heat Dome: a persistent high-pressure system that holds hot air over a region, and intensifies it through sinking air and clear skies. It creates extreme heat that can last for days or even weeks.
Ice Sheet: a glacier that covers an expanse larger than 50,000 square kilometres.
Marine Cloud Brightening: a geoengineering technique that proposes spraying fine sea salt particles into low-lying ocean clouds to make them more reflective, bouncing more sunlight away from Earth.
Mitigation Deterrence: the risk that deploying geoengineering or other climate interventions reduces the urgency and political will to cut greenhouse gas emissions at the source.
Net Zero: the point at which human-caused (or anthropogenic) carbon dioxide emissions are balanced by anthropogenic carbon dioxide removals from the atmosphere.
Ozone Layer: ozone gas in the stratosphere that absorbs the majority of the Sun's harmful ultraviolet radiation.
Path Dependence: how past decisions constrain present choices.
Pathogen: the microorganism that can cause a disease.
Rossby Waves: vast bends in the mid-latitude jet streams that form because Earth’s rotation affects moving air differently at different latitudes.
Sea Ice: frozen seawater that forms on the ocean’s surface and floats there.
Solar Radiation Modification: geoengineering techniques that aim to cool the Earth by reflecting a portion of incoming sunlight back into space before it can warm the surface.
Spillover: when a pathogen passes from its usual animal host into humans. Storm Surges: unusual rises in sea levels caused by a storm's winds and low pressure system pushing water towards land.
Stratospheric Aerosol Injection: a proposed method of solar radiation management that releases reflective particles, like sulfur, into the upper atmosphere to mimic the cooling effect of volcanic eruptions.
Summer Monsoon: a seasonal reversal of wind patterns that brings intense, prolonged rainfall to South and Southeast Asia.
Technology Transfer: the process of sharing skills, knowledge, manufacturing methods, and intellectual property (IP) across national borders.
Termination Shock: the sudden and severe warming that could occur if geoengineering efforts abruptly end. A termination shock would be especially severe if these efforts end when greenhouse gas emissions remain high.
Tropical Cyclones: powerful rotating storm systems that form around a low-pressure center over warm tropical oceans. They are called hurricanes in the Atlantic and northeastern Pacific, typhoons in the northwestern Pacific, and cyclones elsewhere.
Vectors: organisms that carry and transmit pathogens, the microscopic agents of disease, between hosts. Think of fleas carrying plague, or mosquitoes carrying malaria.
West Antarctic Ice Sheet: an ice sheet resting largely on bedrock below sea level. Its loss would dramatically raise global sea levels and could accelerate if its floating ice shelves collapse. One possible, but highly uncertain, possibility is called marine ice-cliff instability, in which newly exposed ice cliffs collapse under their own weight, abruptly raising sea levels.