The cause of the glaciation is heavily debated. The appearance and development of terrestrial plants and microphytoplankton, which consumed atmospheric carbon dioxide, may have diminished the greenhouse effect and promoting the transition of the climatic system to the glacial mode. Though more commonly associated with greenhouse gasses and warming, volcanism may have induced cooling. Volcanoes can supply cooling sulfur aerosols to the atmosphere or deposit basalt flows which accelerate carbon sequestration in a tropical environment. Increased burial of organic carbon is another method of drawing down carbon dioxide from the air.Two environmental changes associated with the glaciation were responsible for much of the Late Ordovician extinction. First, the cooling global climate was probably especially detrimental because the biota were adapted to an intense greenhouse. Second, sea level decline, caused by sequestering of water in the ice cap, drained the vast epicontinental seaways and eliminated the habitat of many endemic communities.