Because as we all know, you can never never never never never NEVER NEVER NEVER NEVER NEVER NEVER NEVER EVER EVER EVER EVER EVER EVER EVER EVER EVER EVER increase taxes, because that would be BAD and there might be unforseen economic consequences to doing so.
GENEVA (Reuters) - "Climate engineering" projects, such as spraying seawater into the sky to dim sunlight, would be a more effective brake on global warming than increasing taxes on energy, a group of economists said on Friday.
Led by Bjorn Lomborg, a Danish statistician and author of "The Skeptical Environmentalist," a book which questioned orthodox environmental views, the group ranked "cloud whitening" as a top option in combating climate change. "Climate engineering could provide a cheap, rapid and effective response to global warming," the economists said.
Lomborg's panel ranked research into "marine cloud whitening technology" -- having boats spray seawater droplets into the sky to create clouds -- as the best of 21 ideas reviewed.
They ranked more research into clean energy such as solar and wind power second, ahead of research into spewing tiny dust-like particles high into the atmosphere to block sunlight and research into burying greenhouse gases. Among the least promising solutions, the group said that: "carbon taxes would be an expensive, ineffective way to reduce the suffering from global warming."
EDIT
http://www.reuters.com/article/environmentNews/idUSTRE58307720090904