Growth in global GDP increases energy consumption in the near term but reduces GHG emissions over the longer term. Economic growth promotes urbanization, education of women, delay of childbearing, lower fertility rates, improved agricultural productivity, and technological innovation. These developments ultimately reduce emissions via fewer humans, more land available for wild habitat and reforestation, and increased energy efficiency. As economies become increasingly affluent, urban and service-based, further reductions in emissions are achieved through changes in transportation and consumption patterns. Healthy and growing economies will also be able to generously fund R&D to continually improve on ways to reduce energy intensity and carbon intensity of energy consumption. Sounds a bit too idealized? These processes are already happening. For instance, in the US energy intensity – measured as energy consumption divided by GDP - has been dropping for decades. Carbon intensity has been dropping as well. A carbon tax would help quicken the pace of change. Of course, a carbon tax would need to be phased in gradually so as not to disrupt economic growth.
Reference:
Carbon vs. Energy Intensity; posted on January 14, 2013 by Maximilian Auffhammer (the George Pardee Professor of International Sustainable Development at the University of California Berkeley). https://energyathaas.wordpress.com/2013/01/14/carbon-vs-energy-intensity/