(2007) concluded, with very high confidence, that regional temperature trends had already affected species and ecosystems around the world (p. 792). With high confidence, they concluded that climate change would result in the extinction of many species and a reduction in the diversity of ecosystems (p.
Full Answer. Use of the Gregorian calendar keeps the arrival of spring on March 20 or March 21 for most years, though sometimes spring arrives on March 19. According to National Geographic, in addition to the astronomical start of spring, a biological spring begins each year, usually on a different date.
The United States is in the Northern Hemisphere, so summer is from June to August. (Technically June 21 to Sep. 21). Spring is therefore March-May (technically March 21 to June 21). The solstice days are the official boundaries, but it's more about weather than dates. In terms of complete months, in most north temperate zone locations, spring months are March, April and May, although differences exist from country to country. (Summer is June, July, August; autumn is September, October, November; winter is December, January, February). Written Jan 7.