Rising temperature, decreasing income?

Hotter means lower income, even within countries, but there is a theory of longer-term adaption. 

From a new NBER paper, "TEMPERATURE AND INCOME: 

RECONCILING NEW CROSS-SECTIONAL AND PANEL ESTIMATES":

This paper provides new evidence on the relationship between temperature and income. 

Using sub-national data from 12 countries in the Americas, we show that the negative cross- 

sectional relationship between temperature and income exists within countries, as well as across 

countries. We then provide a theoretical framework for reconciling the substantial, negative 

association between temperature and income in cross-section with the even stronger short-run 

effects of temperature shown in panel models. The theoretical framework suggests that half of 

the negative short-term effects of temperature are offset in the long run through adaptation.