Politicians who deny human-caused climate disruption elevate their own opinions above the expertise of not only climate scientists, but biologists, physicists, chemists and ecologists. It's as arrogant and inexplicable as claiming they know more about how to launch rockets than NASA, more about building skyscrapers than architects and more about computers than geeks.

A new report will now force these politicians to conclude they also know more about health and medical science than doctors. Next time they have chest pain we should hand out scalpels and insist they do their own open-heart surgery.

A new report released jointly by the Lancet (the most prestigious medical journal in the United Kingdom) and numerous departments of the University College London outlines anticipated global public health consequences of climate change. The lead author said, "The big message of this report is that climate change is a health issue affecting billions of people, not just an environmental issue about polar bears and deforestation. The impacts will be felt ... in our lifetimes and those of our children."

These public health experts warn of increased transmission of tropical diseases such as malaria, West Nile virus and dengue fever, as well as more frequent killer heat waves like the one in Europe during July 2003 that killed 70,000 people.

Already more than a billion people suffer malnutrition and inadequate clean water resources. Summer temperatures in Australia and India are expected to exceed 120 degrees. Half the world's population is likely to face severe food shortages from climate disruption. Accessible clean water will be further diminished by disappearing glaciers and the consequences of fatal and debilitating gastrointestinal diseases will spread.

Increases in the frequency and severity of hurricanes, cyclones, fires, floods and droughts will result in frequent public health crises. Large-scale population migration will be inevitable, resulting in civil disorder, if not outright war, as in Sudan.

As people flee areas made uninhabitable by hotter temperatures or destroyed by extreme weather events, they not only place heavy demands on the ecosystems and social infrastructures into which they migrate, but also carry illnesses that emerge from shifts in infectious disease vectors. Think swine flu on steroids.

Another recent medical report calculated that the decrease in air pollution from reducing fossil fuel combustion by 50 percent could save 100 million lives by 2050.

No one is faster to the courtroom than Americans when they think they have been harmed by someone else. Yet, many of us are indignant at the suggestion that the American carbon-intensive lifestyle is already responsible for endangering entire nations (Dick Cheney famously said the American lifestyle was non-negotiable). But we are on course to cause unimaginable suffering, disease and loss of life to billions of people in poorer nations, and to future generations everywhere.

Rationalizing our behavior by claiming that the science isn't in yet is a cowardly response. Add medical science to the other disciplines that no longer allow us that refuge.

If a 2-year-old old runs out in the street, responsible parents don't react when it's convenient, and they don't wait for absolute proof that the child will be killed by a car before they whisk their child from danger.

Waiting until it's economically convenient, or demanding absolute proof that your carbon emissions will kill others before you act, is just as irrational, immoral and indefensible.

The authors of the Lancet report state, "The inequity of climate change -- with the rich causing most of the problem and the poor initially suffering most of the consequences -- will prove to be a source of historical shame to our generation if nothing is done to address it."

The Utah Physicians for a Healthy Environment found Gov. Jon Huntsman Jr. to be a supportive partner. We think he was asked to serve as ambassador to China because he understands climate change, the immorality of carbon emissions from business as usual, and the key role China must play in mitigating the looming global health catastrophe.

Public statements from our soon-to-be governor, Gary Herbert, are cause for concern. We ask him to take a page from Huntsman's playbook. Accepting science has become a moral imperative and the centerpiece of real family values, especially if "family" means the entire human family, and "values" means life itself.

Dr. Brian Moench is president of Utah Physicians for a Healthy Environment.