BlackRock, the world's largest fund manager, has announced that it will divest over $500 million in thermal coal shares from its actively managed portfolios, citing climate change as a key investment risk. This move may have significant implications for the coal industry and the broader economy, particularly in countries like Australia that are heavily reliant on coal exports. The decision is seen as a sign of the growing trend towards environmentally responsible investing and the increasing pressure on companies to address climate change. As a result, the Australian government's AAA rating may be at risk due to its lack of action on climate change.