Two scientists who advised the Environmental Protection Agency (EPA) have resigned over Donald Trump’s environmental policies.

Dr Carlos Martin, a senior research associate at the Urban Institute, and Dr Peter Meyer, President and Chief Economist of The EP Systems Group, both resigned citing political reasons.

As Mr Martin told The Independent, he simply could “not be a future prop for bad science".

Mr Martin posted their joint resignation letter on Twitter, and in it the pair said they felt the EPA was “watering down credible science” by putting politics where it did not belong.

On several occasions, Mr Trump has called climate a "hoax" perpetrated by the Chinese and is considering withdrawing the US from the global Paris Agreement on climate change. The US is one of the world's top emitters of carbon dioxide.

Mr Meyer and Mr Martin were members of the Sustainable and Healthy Communities subcommittee of the Board of Scientific Counselors (BOSC) at EPA. The board, including all subcommittees, advises EPA scientists on various topics.

In the letter they detail the reasons for their immediate resignation, prompted by non-renewal of two BOSC members who served as co-chairs of their subcommittee.

On 5 May Dr Robert Richardson, a professor at Michigan State took to Twitter with an announcement. He had been “trumped” from his position.

Dr Courtney Flint, a professor at Utah State University also received notice that her term on BOSC would not be renewed.

An EPA spokesperson said they would be replaced by those in industry "who understand the impact of regulations on the regulated community".

Mr Meyer told The Independent that “non-renewal is just a polite way of saying fired”.

BOSC and subcommittee members are nominated by peers if they have significant scientific endeavours and have done research in the environmental field. Once approved, they normally serve two three-year terms.

Ms Flint and Mr Richardson’s first term expired on 27 April, but they were expecting to be renewed. They were not political appointees under the previous Obama administration, but chosen for their scientific and research expertise.

As chairs of the subcommittee, they would coordinate recommendations and reports written by Mr Meyer and Mr Martin and present them to EPA scientists.

The decision to not renew their contracts was likely not financial despite Mr Trump’s 28 per cent proposed budget cuts to EPA, Mr Meyer said.

Lisa Murray's climate change photography Show all 12 1 /12 Lisa Murray's climate change photography Lisa Murray's climate change photography Dinka cattle herders starting their migration in South Sudan Lisa Murray Lisa Murray's climate change photography A Dinka woman fetches water in South Sudan Lisa Murray Lisa Murray's climate change photography Veronica in South Sudan preparing tea outside her home, recently ravaged by heavy flooding Lisa Murray Lisa Murray's climate change photography Children playing in Vietnam. When it floods, transport to and from school is a major challenge Lisa Murray Lisa Murray's climate change photography Sugeng, a fish and crab farmer from Indonesia who suffers financially every time the area floods Lisa Murray Lisa Murray's climate change photography Tan, a vegetable farmer, learning new methods through Oxfam in Vietnam Lisa Murray Lisa Murray's climate change photography Maluk, a 19-year-old from Tonj South, South Sudan Lisa Murray Lisa Murray's climate change photography Normally this farmer in South Sudan would be harvesting sorghum, but rains are late so the hunger season continues Lisa Murray Lisa Murray's climate change photography Herders bringing home their cattle in Afar, Ethiopia Lisa Murray Lisa Murray's climate change photography Farmers harvesting chilli in Ethiopia Lisa Murray Lisa Murray's climate change photography A woman in Tigray, Ethiopia, scares birds away from her crops with a slingshot Lisa Murray Lisa Murray's climate change photography Irula tribe woman in Tamil Nadu Lisa Murray

The Office of Research and Development within EPA, to whom BOSC reports, would likely suffer a 40 per cent budget cut should Mr Trump's budget get approved.

Mr Meyer is an economist and Mr Martin is an engineer by trade, so BOSC and their subcommittee in particular are multidisciplinary in order to best serve EPA scientists holistically in “making science serve you more cost effectively,” as Mr Meyer explained.

He explained that subcommittee and BOSC members made approximately $50 (£38) per hour for their consulting. They met for two to three days a year and worked some hours remotely in order to provide recommendations but Mr Meyer said it did not add up to “significant dollars.”

“The only reason for new leadership is to undermine what we're doing,” he said.

Mr Martin said the decision to resign rather than let their terms expire was because they felt a “sense of confusion and lack of clarity about our future”.

In addition to Mr Richardson and Ms Flint, seven other BOSC members contracts have ended that covered topics like air quality, fracking, and chemical safety.

Mr Meyer’s assumption is that agency administrators will “get rid of all of us” since many people’s terms are expiring.

Given that EPA head Scott Pruitt does not believe that humans cause climate change and Mr Trump's promise to bring back the coal industry, the question remains who will be nominated to take over on BOSC and the subcommittees.

Mr Meyer and Mr Martin both said they were only able to guess but do not doubt that the new members will be somewhat politically motivated nominations.