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.
Earth's atmosphere also play a vital role in regulating the temperature by providing a blanket of gases that not only protects us from excessive heat and harmful radiation from the sun, but also traps heat rising from the Earth's interior, keeping us warm. The average temperature on Earth is about 61 degrees F (16 C). But temperatures vary greatly around the world depending on the time of year, ocean and wind currents and weather conditions. Summers tend to be warmer and winters colder. Also, temperatures tend to be higher near the equator and lower near the poles. Temperature extremes