Kimiyyar ƙasa
Zan ɗauki wannan takarda a matsayin maƙala ta waƙa game da Duniya.
— (1962)
Har yaushe Duniya za ta iya ci gaba da zama kore? Climate model ya ba da kewayo, ba ranar ƙarshen duniya ba
Three-dimensional climate simulations 29 sun sanya limits daban-daban ga photosynthetic biosphere na Duniya tsakanin kusan biliyan 1.35 da 1.87 daga yanzu. Ƙimomin suna dogara da paths da aka sauƙaƙa da gangan na rock weathering, zafi da mafi ƙarancin carbon dioxide da plants za su iya amfani da shi. Ba forecast ba ne na lokacin da duk plants, duk life, civilization ko Duniya za su ƙare.
Thin, half-molten first crust: model inda impacts, ba internal heat ba, suka tafiyar da Hadean
First eon na Earth, Hadean, ya bar almost no rock record. Wannan modelling study ya tambayi yadda crust zai kasance idan ka daina ignoring impacts. Ta stochastic declining impact-flux model da benchmarked simulations na crust da mantle heat flow, authors sun find impact heat would exceed entire internal heat na Earth by at least an order of magnitude ga most Hadean, yana bar thin crust (under ~5 km) partially molten few kilometres down — too weak, suna argue, for plate tectonics, kuma prone to recycling into mantle, wanda zai explain why so little Hadean material survives. As impacts waned after ~3.9 Ga, lasting continental crust could form around when oldest surviving felsic rocks appear — “likely not a coincidence.” Saboda conservative lower-bound heating, qualitative result robust ne even though exact numbers not fixed. Strong coherent model ne na infancy na Earth — ba direct observation ba.