Higher labour productivity means higher production. Higher production means higher consumption, which almost certainly means more greenhouse gas emissions, which will bring on climate disaster. To support the poor redistribution is needed – from the polluters (the affluent) to those that pollute less (the poor).
More detail…

It is possible to improve production so that it emits less greenhouse gasses for each unit of production. e.g. it is possible to change manufacturing techniques and energy generation so that making a car or building a house emits less greenhouse gasses than it did last year. This measure is called the carbon intensity of production. (“Carbon intensity” because greenhouse gasses are measured in relation to the main GHG, carbon dioxide.)
The rate of change of greenhouse gas emissions increases with the rate of economic growth. It decreases if carbon intensity is decreased. The problem is that when the world has emitted a certain amount a limit is reached and climate disaster happens. To keep within this limit in the coming decades means decreasing emissions extremely fast – at a rate that cannot be achieved without decreasing output as well as its carbon intensity. We need to decrease carbon intensity, production and consumption. i.e. de-growth.
See “Jobs and climate change” (http://ow.ly/1081WS )