Warming planet has big effect on weather, economy

This is the time of year when we tend to look inward and ask ourselves if there’s a way to improve our lives. In the spirit of the New Year, let’s take a look from outer space.

Many of the satellites orbiting above look inward, toward Earth. For the past three decades, the National Oceanic and Atmospheric Administration has had satellites in polar orbits that measure the heat radiated from Earth into space, which is directly correlated with the average temperature of the air and ocean or land just below it.

These and other data show that our planet has warmed about 2 degrees Fahrenheit over the past century. Similar measurements by satellites launched by the European Space Administration agree.

Though 2 degrees doesn’t sound like much, it can have a big effect. For example, the ice sheet covering the north pole has been shrinking consistently, reaching record low levels in the past few years. At the south pole, record melting has resulted in large ice sheets breaking off and 400 million tons of ice being converted to water each year. Without a doubt, sea levels are rising.

Perhaps, living in Ohio, rising sea levels don’t directly affect you. But there are real economic consequences of climate change.

Computer models of hurricanes show that higher ocean temperatures result in bigger storms than would occur if the oceans were even 2 degrees cooler. The two most damaging hurricanes that hit the U.S. during 2018 were Florence and Michael, which were estimated to cost $50 billion and $25 billion in damages, respectively. This cost is paid by U.S. taxpayers.

Add to this the fires in California, which cost insurance companies $16 billion in 2018, not to mention the firefighting and federal assistance costs. Those fires added to the cost of homeowners insurance and taxes nationwide. Climate models show that the fire season would be shorter if global temperatures were lower.

Though politicians in Washington can’t seem to get much done on this issue, there are things that both private industry and the public can do to help reduce the warming trend, such as buying fuel-efficient vehicles and supporting initiatives for electricity production from renewable sources, such as wind and solar.

In the long term, the future of the human race might be at stake. We only need to look at the other planets to see what can occur if the delicate balance of nature’s thermostat is upset.

Venus orbits the sun with a radius about threequarters that of Earth, yet it has a surface temperature of 864 degrees Fahrenheit, higher than Mercury’s. The reason is that the atmosphere of Venus is about 96 percent carbon dioxide. The more carbon dioxide in the atmosphere, the more heat is trapped, and the hotter the planet. (Mercury has almost no atmosphere.)

Before about 1950, stretching back to 400,000 years ago, the carbon dioxide level in Earth’s atmosphere never exceeded 300 parts per million. We know this from air bubbles trapped in ice far below the surface at the south pole. Today, Earth’s atmosphere has more than 400 parts per million. The only explanation is the burning of fossil fuels.

In the past, I’ve taught a course on the possibility of extraterrestrial life existing in the universe. One of the crucial questions I asked in that course: If intelligent life came to exist on a planet, what would be its life span? We could reflect inward and ask the same thing about the life span of the human race.

Kenneth Hicks is a professor of physics and astronomy at Ohio University in Athens. hicks@ohio.edu