In Part 1 of “A Conversation with Hank Brown” (Daily Camera, Feb. 8), Senator Brown unfortunately made a number of remarks concerning climate change and solar energy that are not consistent with the scientific facts. Below are a few of those remarks followed by a brief description of what science tells us:

“So climate change and warmer periods and colder periods are a normal part of the cycle that the Earth goes through.”

While this statement is true, the implication that the current rapid warming is natural certainly is not. When climate scientist Michael Mann published his work showing that the recent warming is unprecedented, his so-called “hockey stick” curve (which shows a sharp upturn after we began burning fossil fuels) was widely criticized by those anxious to discredit the scientific findings. As a result, Congress commissioned the National Research Council to review these findings. In a 160-page 2006 report, they not only supported Mann’s result but found many other sources of data indicating that the current warming of the Northern Hemisphere is unprecedented for at least the last 1,000 years. While various natural forces can affect temperature, it is well documented that our emission of greenhouse gases that trap outgoing infrared radiation are the cause of the present strong global warming trend.

“Well, the portion [of carbon dioxide emissions] that’s man-made of carbon dioxide is minuscule…You also have carbon dioxide from natural causes, from volcanoes and other things.”

There are, indeed, very large natural fluxes of carbon dioxide into and out of the atmosphere, but these have been in balance for thousands of years. While mankind’s addition to the former (about 4 percent) may seem small to some, it strongly drives the system out of balance.

This natural balance kept the atmospheric carbon dioxide level close to 280 parts per million for 10,000 years, corresponding — not coincidentally — to a stable period of temperature and sea level during which human civilization finally had the right conditions to develop. But direct measurements clearly show that our “minuscule” addition has, in fact, suddenly and dramatically increased atmospheric CO2 by 43 percent to 400 parts per million — higher than it has been for at least 800,000 years. We know from the geologic record that such swings in carbon dioxide content lead to enormous effects on temperature and the climate. And while volcanic eruptions do release some carbon dioxide, a 2011 study published by a U.S. Geological Survey researcher concluded that man emits, on average, 135 times as much. Furthermore, the main climatic effect of volcanic eruptions is that they release sulfur dioxide, which temporarily blocks sunlight and thus masks global warming. Volcanoes thus have exactly the opposite effect of the one Senator Brown implies.

“If warming is a problem, solar energy retains more of the sun’s heat than without it…That increases the warmth of the Earth.”

All the energy from all the fuels mankind burns to produce useful energy ultimately winds up heating the Earth. (Because much of the sunlight used by solar panels would have been absorbed anyway, solar energy is actually better in this regard than fossil fuels.) However, studies have shown that this heating effect from energy production is tiny compared to the heating that results from carbon dioxide emissions. Solar energy systems do not emit carbon dioxide (except for a small amount during manufacture) and thus do not contribute to global warming. Switching from fossil fuels to solar and other forms of renewable energy will greatly decrease the warming of Earth. People who install solar panels on their roof can rest assured that they are making an important contribution to the fight against climate change.

“Where you have some ice sheets retreating, you have other ice sheets expanding.We’re not quite yet to the point now where we have a good feel for all of that.”

Published scientific studies clearly show that the ice sheets at both poles (Greenland and total Antarctica) are rapidly losing mass. This has very serious implications for sea level rise.

False or misleading statements about climate change and renewable energy are widely repeated these days. As a result, many Americans still do not understand the seriousness and the urgency of the climate-change problem and how to address it. I believe the more that people are informed about the scientific facts, the more willing they will be to help speed the transition to renewable energy and energy efficiency that is now taking place in the U.S. and around the world and is producing both environmental and economic benefits.

Charles F. Kutscher, Ph.D. is past Chair of the American Solar Energy Society (ASES). He was editor of the 2007 ASES study, “Tackling Climate Change in the U.S.”