Frozen ground occurs when ground temperature drops below 0°C. Permafrost is permanently frozen soil, gravel, and sand below surface
Global temperatures reached 1.46C above pre-industrial levels in 2023. CO2 levels in atmosphere doubled since Industrial Revolution. Greenland ice sheet melting at record rate, threatening 6-meter sea level rise. Ocean acidification causing coral bleaching and reef loss
Tundra is a biome where tree growth is hindered by cold temperatures. Contains dwarf shrubs, sedges, grasses, mosses, and lichens. Soil is rich in nitrogen and phosphorus. Term comes from Russian word adapted from Sámi languages
Mean sea level (MSL) is the average surface level of Earth's coastal waters. MSL is used as a standard datum in navigation and aviation. Sea level varies significantly due to tides, wind, pressure, and temperature
Fossil fuel burning accounts for 89% of global CO2 emissions. Land use change, especially deforestation, contributes 21% of total emissions. Agriculture, especially livestock, is the largest methane source. Energy sector produces around 73% of global emissions
Human activities directly or indirectly affect biophysical environments and ecosystems. Population growth, economic growth, and resource consumption drive environmental issues. Human civilization has caused loss of 83% of wild mammals and half of plants