Near death, we thank you Emporium

What I do here is trace the natural history of a cubic meter of Bangkok air which you might find around, say, Benjasiri Park at 6 am when folks are out there doing Tai-Chi and aerobics. The moisture, temperature, dew point, and enthalpy of the air at 6 am on a reasonably cool March morning is shown as the starting point of the day's oddyssey. The wet bulb temp, ie the temperature of all those dewy flowers across the street at Villa supermarket, is about 24 C, and the enthalpy (ie energy) is a little over 70 KJ per cubic meter. With a relative humidity of about 80 percent, those joggers are going to start to sweat pretty quickly.

It always struck me as curious that the Bangkok air does not change its energy content much over the day, i.e. it is isenthalpic, by afternoon it's a lot hotter but a little drier so energy is much the same. But look what happens to that air if it is lucky enough to get sucked up in the Emporium air con engines which blast off at about 10 am. This air will be cooled down to its saturation point (ie the dew point) and then with further cooling dump about half of it's moisture, so that the nice icy feeling you get when you go into the mall is your own dear sweat getting sucked up by this dry hungry air. It's not the air that's so cold, it's your own vaporizing sweat!
Having said that we can look ahead with delicious dread at the daily cycle at the peak of the hot season now at the end of April, shown in red away up on the diagram. Above the red line, it begins to get dangerous. When and it the morning dew point or daily minimum dry bulb hit 35C, we're all dead.

The colored zones on the chart are so-called comfort zones, green where everyone is happy, yellow where some international experts say folks in "undeveloped" tropical countries should be happy (so they don't use so much of that fuel meant to fire up our big SUVs). Everyone is unhappy in the red zone.

Thank you, Emporium, I think we'll all go shopping!