Heat kills more when it is humid.

By JW Dowey - 06 Jan 2015 18:37:0 GMT
Heat kills more when it is humid.

In the Red Centre of the Aussie desert, this Sturt’s desert pea is an appropriate emblem for survival there. People, however, are suffering, as heat-related deaths increase and humidity could well cause these to increase further. Even the endemic flora and fauna will be hard put to deal with increased global warming, in high humidity and/or scorching heat. Sturt’s desert pea image; Credit: © Shutterstock

With the onset of multiple global warming events, we can only hope they will take place at different times. One of the most obviously neglected areas is hot regions. Both hot desert and tropical forest are often confined to the area of they know all about heat already!

The problem is that both of these 2 extremes are liable to suffer greatly if they are at the limit of their speciesÂ’ tolerance. The trees and the succulents could disappear quickly in such cases, leaving a much more desolate situation than would be imagined in such long-term stable environments. Naturally, we concentrate on areas rapidly becoming desertified or deforestation by industrialists because we can almost watch nature disappearing by satellite.

As a hot continent, Australia is one of many areas providing ideal study of this established set of ecosystems. Scorching weather there as 2015 begins will light the blue touch paper not only for wildfire, but also for severe climatic effects on ecology. Aussies live in cities such as Sydney and Brisbane that are threatened with rising humidity. Summer wind can alleviate conditions cities such as Perth, Adelaide and Melbourne.

The expected (and delivered) extreme heat is studied in The Conversation , following up on the infamous Australian Black Saturday of 2009. An incredible 374 citizens died before those wildfires began, from heat-related stress. In this case Melbourne was the stricken city, to be hit again last year with 167 deaths. This is all apart from the hundreds killed by the raging fires!

Medically, we need to be reminded that sweating rids the body of its heat by evaporation. In high humidity, this is nearly impossible, especially without air circulation or wind. The average person can appreciate this via anapparent temperature. this measurement is rising alongside global warming, giving a higher than reality rise of 1oC. over 60 years for humid Sydney and Brisbane. Western Australia has apparent rises of up to 3oC. (at a staggering 41o C. Muggy conditions affect other Australian cities less, but your own city could well have the same conditions. Monsoons or even high rainfall, for example, will produce terrible humidity. Death rates can obviously follow the pattern shown by the unfortunate Melbourne.

Elsewhere, alarm bells should ring when floods are followed by heat waves. To date, drought has been the worry in California, Texas, SE and SW Europe, Central Asia, the Sahel and parts of South America. If humidity increases, the apparent temperatures in many of these places will exceed even those in Australia. Aid and emergency measures will have to be rapidly sourced from locally-planned supplies and expertise.

To check on global warming generally, but including thousands of heat-related deaths in some cases, we had this article indicating what was likely to happen – and unfortunately, it did!