Trump doubts US government climate report

US president Donald Trump today dismissed the warnings of government scientists that global climate change could significantly damage the US economy, including domestic energy production.

Trump said he is not swayed by the report issued last week by the US Global Change Research Program, a collaboration of 13 federal agencies, predicting broad harm to the US economy unless global efforts to reduce greenhouse gas emissions become more aggressive.

"Yeah, I do not believe it," Trump told reporters as he left the White House this afternoon.

Trump also said action to reduce US emissions could end up hurting the country, suggesting that "China and Japan and all of Asia" will not step up.

"Right now we are at the cleanest we have ever been. And it is important to me. But if we are clean but every other place is dirty, that is not good," he said.

The report, released on 23 November, warned that climate change could cost the US economy hundreds of billions of dollars, unless stronger emissions-reductions begin soon.

"In the absence of more significant global mitigation efforts, climate change is projected to impose substantial damages on the US economy, human health, and the environment," the report says.

The US is already experiencing the effects of climate change, ranging from extreme rainfall and flooding in some areas to drought and increased wildfires in others, according to the report, authored by more than 300 scientists. The severity of these impacts is likely to be much greater if GHG emissions are not curbed, affecting air quality, agriculture, energy systems and transportation infrastructure, the report says.

The findings spurred renewed calls for action by some US lawmakers, mostly Democrats.

"President Trump should heed the message of our nation's preeminent climate scientists and experts: Climate change is a clear and present danger to the health and wealth of the American people," said US representative Frank Pallone (D-New Jersey), who is likely to be chairman of the House Energy and Commerce Committee next year.

Pallone and other House Democrats plan to hold two days of hearings on climate change early next year. But little legislative action is likely, with Republicans still in control of the Senate next year, and with the Trump administration continuing its efforts to curtail US regulation of GHG emissions.

The report offers an indirect rebuke of those efforts. It warns there is "virtually no chance" of meeting the Paris climate agreement's goal of limiting the increase in global temperatures to 2°C if countries deviate from their emissions-reduction pledges, and then notes the US plans to withdraw the US from the accord.

The report does not recommend specific policies or overall emissions reduction for the US, but notes that carbon pricing, such as through a cap-and-trade program, is one option for policymakers.

The congressionally mandated report was the second of two volumes. The first, released a year ago, said GHG emissions from human activity are the "dominant" driver of global climate change.

The report warns that climate change could have significant consequences for the US energy sector, including electricity generation and oil and gas production.

Drought and shifts in snowmelt timing will affect hydropower production in western states, while reducing water available for hydraulic fracturing for natural gas and shale oil in many parts of the country. Higher temperatures and reduced soil moisture will likely make it more difficult to grow crops for biofuel production and affect the availability of woody biomass for heating and fuel.

The report points to recent history for examples of what could happen in the future. The prolonged drought in California led to a 59pc drop in hydropower generation in 2015 compared with the average output of the previous 20 years.

Drought will also affect petroleum refining and electricity generation that relies on water for cooling.