The letter “Electric energy vs. fossil fuels” (Aug.7) pointed out that in 2017 the United States derives 3.1 percent of its energy from wind and solar energy. However, in 2012 we were deriving 1.6 percent of our energy from renewable resources. If the contributions of wind and solar doubles every five years, how long will it take for it to replace most other forms of energy?

The letter also points out the Earth’s climate has been changing forever, which is true. However, the main factors in climate change are small, predictable changes in the Earth’s orbit, which changes the amount of sunlight striking the Earth. On the other hand, the concentration of carbon dioxide in the air has risen by 40 percent in the last decade, which correlates with the generally rising trend in global temperatures, with most areas in the world getting warmer rather than cooler. The claim from the letter is that orbital changes is the cause for these changes does not mention that the Earth is predicted to slowly cool over the next 20,000 years, which has not been displayed by global data in recent years.

The letter also says that the climate will change until the sun is extinguished and all life on Earth will vanish. Life as we know it will vanish much sooner if we do not curb our carbon emissions.