The sed rate test measures the distance red blood cells fall in a test tube in one hour. The farther the red blood cells have descended, the greater the inflammatory response of your immune system.
A woman pulls up her hood as she exits a subway during a snowstorm in New York City, March 5, 2015. Photo: REUTERS/Lucas Jackson. For all practical purposes, winter starts at around the moment your heating fails, forcing you to put on all your ugly Christmas sweaters at the same time. For others, itâs when you slip and fall down a dozen stairs into the subway.
A snow-covered park in Pittsburgh, Pennsylvania, during winter. Winter is the coldest season of the year in polar and temperate climates, between autumn and spring. Winter is caused by the axis of the Earth in that hemisphere being oriented away from the Sun. Different cultures define different dates as the start of winter, and some use a definition based on weather. When it is winter in the Northern Hemisphere, it is summer in the Southern Hemisphere, and vice versa.