Hot Enough For Ya?

Heat could be the big environmental issue of this decade. The Earth is getting hotter. I think we all realize that. The land is getting hotter. The air is heating up. The oceans are absorbing ever more heat (remember, Newton's 2nd law of thermodynamics).  This is easy stuff. We've been using thermometers for a couple of centuries. We've been keeping accurate temperature records for about 140 years.

Heat, however, is taking on some new dimensions. Hotter air, for example, retains more water vapour. That extra humidity, the science types peg it at 14 per cent more, results in severe storm events of increasing frequency, duration and intensity. We're also getting more "atmospheric rivers." These are bands of moisture laden air that snake across our oceans and create heavy flooding when they reach land. Here on the west coast we're familiar with them. We call them the "pineapple express." Now they're showing up in other places such as the UK where the flooding can be even more devastating.

What we're getting today is abnormal. It's taking us by surprise, catching us with our pants down. The UK is a perfect example. There you'll find beautiful, quaint villages built along rivers that are now becoming seasonally inundated.

When these villages were built, flash flooding wasn't an issue. It is now.

The new heat and humidity is also taking a toll on humans. Excess heat and humidity can kill. Extreme humidity can negate evaporative cooling. You still sweat only the air is too humid to wick that moisture away.  The body begins to overheat, damaging internal organs.

The US is broken into three heat bands. The hottest begins along the southeastern seaboard to Florida and then west to the California interior. I'm not sure why the San Diego/Los Angeles coastal corridor isn't included. Within this band the heat and humidity index is being taken seriously as this University of Georgia heat chart for athletics demonstrates.

In other parts of the world, wet heat is a more sinister threat. The areas most affected are countries in the equatorial and tropical latitudes. These tend to be the poorest countries where much of the population works outdoors, usually in agriculture. Working too long in the fields can be a death sentence. Seeking shelter, however, restricts the amount of farm work that can be performed.  For people eeking out a subsistence living this can be a nightmare.

It's not only herders and farmers that are affected.  In tropical Singapore, pandemic healthcare workers are harshly impacted.

Global warming will increase the chances of summer conditions that may be "too hot for humans" to work in. 

When we caught up with Dr Jimmy Lee, his goggles were steamed up and there was sweat trickling off his neck. 

An emergency medic, he's labouring in the stifling heat of tropical Singapore to care for patients with Covid-19. 

There's no air conditioning - a deliberate choice, to prevent the virus being blown around - and he notices that he and his colleagues become "more irritable, more short with each other". 

And his personal protective equipment, essential for avoiding infection, makes things worse by creating a sweltering 'micro-climate' under the multiple layers of plastic. 

"It really hits you when you first go in there," Dr Lee says, "and it's really uncomfortable over a whole shift of eight hours - it affects morale."

And as Dr Lee and other medics have found, the impermeable layers of personal protection equipment (PPE) - designed to keep the virus out - have the effect of preventing the sweat from evaporating.

For some healthcare providers help may be on the way where it's feasible and, more critically, where it's affordable.



In impoverished regions, personal cooling systems would be prohibitively expensive for agrarian workers. There, options will narrow.