One of the better signs at last year’s March for Science Iowa featured dear old Darwin. Credit: Paula Mohr.

Iowans have an opportunity to hear from a hero in the battle to halt or reverse climate change.

The event is the annual Iowa City Darwin Day, actually a two-day symposium to honor Charles Darwin, the naturalist whose book, “On the Origin of Species,” posited evolution as an explanation for the diversity of life on Earth. The celebration is held every year on or around the great scientist’s February 12 birthday. This year it’s Friday and Saturday, February 23-24, on the University of Iowa campus.

Darwin Day celebrates science – particularly science that often is denigrated or attacked, such as evolution and human-caused climate change. Many of the sessions revolve around these two subjects and how to communicate about them with skeptics.

This year’s program includes a rare chance to see in person a former Iowan who has become a champion and a lightning rod on climate change.

James Hansen has been hailed and reviled for blowing the whistle on climate change. He studied under the great James Van Allen at the University of Iowa in the post-Sputnik heyday of space science and went on to direct the NASA Goddard Institute for Space Studies. As Hansen explains in this Des Moines Register piece, his interest in how excessive carbon dioxide can alter a planet’s atmosphere originated with Van Allen’s observations on Venus’s hellish climate. In Venus’s past, Hansen saw Earth’s future if CO² concentrations continue to rise. His research (and that of many other scientists) led Hansen on a crusade to replace dirty fuels such as coal with renewable energy such as wind and solar.

Yet Hansen is not universally loved among climate change activists. He has embraced nuclear energy as perhaps the best, fastest way to cut greenhouse gas emissions while continuing to meet world energy demand. Not everyone is happy about that.

Hansen will address “Energy, Climate and Policies: Risks and Opportunities” on Friday at 4:45 p.m. in the Biology Building’s Kollros Auditorium.

The other speakers are stellar, too: Jacquelyn Gill of the University of Maine Climate Change Institute Asheley Landrum, a strategic science communication professor at Texas Tech University; and Paul Strode, a high school science teacher from Boulder, Colorado. He’ll give a talk and host a workshop for teachers, each on getting students to think like scientists. Teachers who attend can earn continuing education credits.

Check out the full schedule at the Darwin Days website.