The big oil companies told me we shouldn't delay action against manmade climate change. At least that's what I read on their websites.

For now, the EPA's climate regulations remain intact. Earlier this month, the House voted to block those rules, but the Senate rejected a bill to do that. And a House-approved rider to stop the regulations was dropped in a last-minute compromise on the 2011 budget bill.

Many in Congress, including members of the Texas delegation, are expected to keep up the fight against the rules, but when it comes to the need to reduce emissions of greenhouse gases (GHGs), there doesn't seem to be much disagreement — at least not among the major oil and chemical companies.

Consider three of the biggest - Chevron, ExxonMobil and Shell. They've all moved toward growing support for climate action, judging from a comparison of what they posted on their websites in 2000 and what is there today.

For example, in 2000 Chevron said it understood the "concern" that increased GHG emissions would alter the climate, but "share[d] the view of many scientists that the link between the increase in greenhouse gases and potential climate change is uncertain."

In 2001, Chevron replaced that statement about scientific uncertainty with a declaration that "concerns are growing about global warming." Even before then, the company had started implementing its own Climate Change Action Plan "to manage and reduce GHG emissions."

In 2000, ExxonMobil's website said it had "studied climate change for nearly two decades" and did "not believe that the current scientific understanding justifies mandatory restrictions on the use of fossil fuel." The next year, it acknowledged that "enough is known about climate change to recognize that it may pose a long-term risk."

By 2010, the company's risk assessment was much more definitive: "[T]he risks to society and ecosystems from increasing GHG emissions are significant. … We must all engage in the search for solutions."

In 2011, ExxonMobil says it is "prudent to develop and implement strategies that address the risks to society associated with increasing greenhouse gas emissions."

Their website now includes charts developed by the U.N.'s Intergovernmental Panel on Climate Change (IPCC), whose conclusions are much maligned by skeptics, including top Texas officials. I could find no website indications, however, that ExxonMobil shares such doubts about climate science. In fact, it is not uncommon for the company to note its GHG reductions in quarterly statements to shareholders.

In 2000, Shell had this to say:

"At the very least, mankind is carrying out a risky experiment with the planet by raising the levels of greenhouse gases in the atmosphere to levels far above any seen in the last 150,000 years or more. We do not know whether this will be catastrophic, or whether it might on balance be slightly beneficial. But we do know that it is, in effect, irreversible. It makes sense, therefore, to take prudent precautionary measures now."

In 2010 Shell became more direct, saying that as far as it was concerned, "the debate on climate change is over." The company said it "… continue[s] to develop technologies to reduce [carbon dioxide, the principal human-produced greenhouse gas] from our operations and to produce more efficient fuels and lubricants for our customers. We are calling on governments to establish policies that will encourage a reduction in CO2 emissions."

The common thread for these and other petrochemical companies is a clear shift away from statements saying "we believe" or "we don't believe" to statements that essentially read, "This is what we have done and are planning to do to reduce greenhouse gases."

The major oil and chemical companies, which have many scientists and engineers with considerable expertise, have already determined that reduction of greenhouse gases is important and are working on the problem.

However, federal and state officials need to provide oversight and verification of industry's emission reductions. Government entities are needed to ensure there is a level playing field for the highly competitive petrochemical and electric power companies.

I share the concerns, held by many, that any greenhouse-gas reductions we achieve in the U.S. will be negated by the economic growth and increased emissions in places like China and India. However, the U.S. has led the world for well over 50 years in economic growth, fossil-fuel consumption and greenhouse-gas emissions.

It's time we formally recognize what the major petrochemical companies say on their websites - that greenhouse-gas emissions pose risks to society. We need to become the leaders in economic growth while simultaneously reducing greenhouse gases.

Reducing the risks associated with higher greenhouse-gas emissions won't be easy or free, but this is an investment in the future that we cannot afford to pass up. The EPA's new regulations to reduce these emissions at major industrial facilities are not perfect. I personally would do some things differently. But if someone opposes those regulations thinking there's still some overwhelming uncertainty regarding the science of manmade climate change, then they hold a view that's counter to what the major oil companies say. So let's go on and get something done.

We could spend a long time in congressional debates and legal battles, but let's move forward, as if the lives of our children and grandchildren depend on it.

Because they do.

Cuclis is a research scientist at the Houston Advanced Research Center in The Woodlands.