Study: Space tourism could drive climate change

“Rockets are the only direct source of human-produced compounds above about 14 miles, and so it is important to understand how their exhaust affects the atmosphere,” said Martin Ross, an atmospheric scientist from the Aerospace Corp. and the study’s lead author, in a statement.

“A global climate model predicts that emissions from a fleet of 1,000 launches per year of suborbital rockets would create a persistent layer of black carbon particulate in the northern stratosphere that could cause potentially significant changes in the global atmospheric circulation and distributions of ozone and temperature,” the paper said.

According to a summary of the findings from the American Geophysical Union (AGU), which publishes the journal, the black carbon could prompt some surface cooling, though Antarctica would warm even more.

“Some parts of the earth would get cooler, some would get warmer; the net effect is to add solar energy to the atmosphere,” Ross told The Hill.

Ozone, meanwhile, would decrease by 1 percent in equatorial regions while increasing about 10 percent in polar regions, according to the AGU.

“The globally integrated effect of these changes is, as for carbon dioxide, to increase the amount of solar energy absorbed by the earth’s atmosphere. In this case, as long as the launches continue at the assumed rate, soot from the suborbital rockets contributes to atmospheric heating at a rate significantly higher than the contribution from the carbon dioxide from those same rockets,” the group said.

Ross said the paper highlights the need to consider the climatic effects of the fledgling industry. “We really don’t know exactly what is going on here. What we have done with our paper is say, ‘Hey, here is something we may want to pay attention to. Here is something we should probably learn more about.’

“We want to get the facts before anybody … starts making unnecessary regulations or overly conservative regulations.”

Ross said that in coming months — tentatively, late this year or in January — the Aerospace Corp. plans to convene a workshop on the issue that will bring together scientists, engineers, policymakers and other stakeholders. “This is going to be a big tent. We want everyone to understand each other,” he said.

Ross wrote the paper with co-authors from the University of Colorado and the National Center for Atmospheric Research in Colorado.

The Aerospace Corp. and NASA funded the research. The corporation is a federally funded nonprofit company that provides guidance and advice on space missions to the U.S. Air Force and other agencies.