Documents show that Professor Bob Carter, a leading climate change sceptic  is paid a monthly retainer by the US Heartland Institute.

Heartland is a conservative think tank, and is paying Carter $US20,000 as part of a program to pay "high-profile individuals who regularly and publicly counter the alarmist [anthropogenic global warming] message".

Here's an extract from Wikipedia on Heartland:

In the 1990s, the group worked with the tobacco company Philip Morris to question the science linking secondhand smoke to health risks, and to lobby against government public health reforms.^[6][7][8] More recently, the Institute has focused on questioning the scientific consensus on climate change, and has sponsored meetings of climate change skeptics.

Carter writes regularly for News Ltd.