The demand for air quality depends on health impacts and defensive investments that improvehealth, but little research assesses the empirical importance of defenses. We study the NOxBudget Program (NBP), an important cap-and-trade market for nitrogen oxides (NOx) emissions,a key ingredient in...

In the absence of significant greenhouse gas (GHG) mitigation, many analysts project that atmospheric concentrations of species identified for control in the Kyoto protocol could exceed 1000 ppm (carbon-dioxide-equivalent) by 2100 from the current levels of about 435 ppm. This could lead to...