Education. If you want to become an optometrist, you'll need about eight years of education. Depending on how fast you work, you might be able to graduate sooner if you take on additional credit hours or complete coursework during the summer.
Although the results for the Earthâs temperature are usually given as anomalies, climate scientists have used the measured temperature data to calculate average temperatures. NOAAâs result for the 20th century average land-ocean Earth surface temperature is 13.9 Â°C. The 2011 NOAA surface temperature anomaly of 0.51 Â°C, gives an average Earth temperature of 14.4 Â°C for 2011. To find out more about how the Earth is warmed and the greenhouse gases that are responsible, see How Atmospheric Warming Works and Greenhouse Gases.
The global average surface temperature rose 0.6 to 0.9 degrees Celsius (1.1 to 1.6Â° F) between 1906 and 2005, and the rate of temperature increase has nearly doubled in the last 50 years.Temperatures are certain to go up further. Despite ups and downs from year to year, global average surface temperature is rising.By the beginning of the 21st century, Earthâs temperature was roughly 0.5 degrees Celsius above the long-term (1951â1980) average. (NASA figure adapted from Goddard Institute for Space Studies Surface Temperature Analysis. ).lobal warming is the unusually rapid increase in Earthâs average surface temperature over the past century primarily due to the greenhouse gases released as people burn fossil fuels.