Combinations of increased heat and humidity will render portions of the Earth uninhabitable. In fact, I have visited two places already in this situation: Daharan, Saudi Arabia, and Monterrey, Mexico. In both places, prolonged work outside was impossible. Even heat-adapted people cannot carry out normal outdoor activities past a wet-bulb temperature of 32 °C (90 °F), equivalent to a heat index of 55 °C (130 °F)². The human body can't tolerate wet bulb temperatures that cross 35°C ¹. In other words, humans can no longer live when the peak wet bulb temperature reaches 35c. The chart below is in Fahrenheit, but the black zone is clear. I particularly note the wicked combination of humidity and temperature. As I write, humidity is 87% in Vancouver. Dangerous heat would be at just 80 degrees F. That's what we called a "heat dome" recently.

  Carbon Offsets Explained to the Kiddies (or " Pickle #4") John Oliver presents a funny but true overview of "Carbon Offsets" here . As he points out, the whole thing is a hoax. But it's much worse than he says. It wouldn't work even if it were not a hoax. Planting a tree takes C02 out of the atmosphere as it makes roots, barks and leaves out of the carbon it "breathes in".  But this is a one-time thing . The "carbon offset" idea is based on the tonnage of vegetable matter created by the tree, not the entire life cycle of the tree. The Amazon forest emits more C02 than it absorbs on a net basis. So, for example, the " trillion tree campaign ", in theory, would offset a tremendous amount of carbon once . Next year, we'd need another trillion trees to be planted (or, absurdly, not cut down). As John Oliver puts it, we can't offset our way out of climate change. Even if we could, the idea is fundamentally flawed. In the ...

All processes that do "work" ultimately release "waste" heat into the environment. The heat grows with economic activity, namely GDP. Before too long, this effect rivals GHG as a source of "extra" heat, so any assumption of economic growth must eventually deal with this issue. This may actually deserve to be another unwelcome adjustment to the Keya identity, or we can simply assume that we account for *all* forms of heat generated by "carbonized" energy -- over and above GHG "greenhouse" forcing. Many economic models assume significant GDP growth for the rest of the century. The heat generated by this growth might easily cancel out gains achieved by decarbonization, optimistically around 10%. All these KWh are released as heat. The heat generated from solar cells or windmills is not "extra" since it simply re-directs solar heat that would be present in any case. But the heat from burning fossil fuels or nuclear technology is a...

The Kaya Identity tells us exactly what families of tools we have in the policy toolbox to reduce carbon dioxide emissions to some desired level. Specifically, carbon dioxide accumulating in the atmosphere can be reduced only by influencing the following four levers.  1. We could reduce the population.  2. We could reduce per capita GDP. 3. We could become more efficient.  4. We could switch to less carbon-intensive sources of energy.  These are the four—and the only four—means of reducing carbon dioxide emissions. All policies being discussed as climate policies must influence these levers if they are to have an effect. So debates about carbon taxes, cap-and-trade programs, offsets, energy innovation, personal carbon allowances, and on and on, must eventually arrive exactly the same place.  Kaya Identity (1) Carbon Emissions = Population * Per Capita GDP * Energy Intensity * Carbon Intensity a. P = Total Population b. GDP/P = Per capita GDP (2) GDP = Economic G...