The Labor Party will ignore adopting a progressive policy on climate change at its peril, former leader Mark Latham has warned.

He says the party is ''not dead yet'' but it still has to accept that it is dominated by its union base at a time when the union movement has never been more irrelevant.

Former ALP leader Mark Latham. Credit:Jessica Hromas

''The processes of government have resulted in greater transparency about the true state of the labour movement,'' Mr Latham writes in the latest edition of Quarterly Essay, released on Monday.

''The ALP's rank-and-file membership has collapsed, concentrating power in an oligarchy of union-based factional leaders,'' he writes.