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.
Article and Chart Updated: January 28, 2017. Until late 2006, global temperatures were more than a degree Fahrenheit warmer when compared to the 20th Century average. From August of 2007 through February of 2008, the Earthâs mean temperature dropped to near the 20th Century average of 57 degrees.