"South-South" trade among developing countries is increasing, and helping to reduce China’s emissions by shifting energy-intensive production to less developed regions. But this may make climate mitigation more challenging; emissions are spread among more and less-developed countries.

Differences in Chinese cities’ carbon intensity are largely due to disparities in economic structure that can in turn be traced to past investment-led growth. Related carbon lock-in may hinder China’s efforts to reduce emissions from activities in urban areas.

Analysts and markets have struggled to predict a number of phenomena in U.S. energy markets over the last decade or so, such as the rise of natural gas. I explain new research that shows this may be a result of the industry--and consequently the market--becoming increasingly volatile.

Analysis of hourly weather data shows that meeting >80% of U.S. electricity demand with only solar and wind would require days' or weeks' worth of energy storage--even assuming a continental-scale transmission grid. Today this would be very costly.