Photo: Cinty Ionescu - BY-NC

Humans can only survive below a threshold of 35°C

Middle East, North Africa and Southern European levels of intense heat could make outdoor work very difficult this century and human life impossible around the Arabian Gulf.

A study in the science magazine Nature explains that the human body may be able to adapt to extremes of dry-bulb temperature (commonly referred to as simply temperature) through perspiration and associated evaporative cooling provided that the wet-bulb temperature (a combined measure of temperature and humidity or degree of ‘mugginess’) remains below a threshold of 35°C. This threshold defines a limit of survivability for a fit human under well-ventilated outdoor conditions and is lower for most people. Using an ensemble of high-resolution regional climate model simulations, the study projects that extremes of wet-bulb temperature in the region around the Arabian Gulf are likely to approach and exceed this critical threshold under the business-as-usual scenario of future greenhouse gas concentrations. The results expose a specific regional hotspot where climate change, in the absence of significant mitigation, is likely to severely impact human habitability in the future.

Other studies show that rising temperatures will affect the health and productivity of workers in Europe as well as in the world’s hottest regions, CNW reports. We are hot, we are tired, and we work less, the studies say. Rising temperatures caused by climate change that result in higher temperatures in the workplace will also lead to a significant drop in economic productivity. Ongoing studies into the impact of rising temperatures on various economic sectors suggest that the productivity reduction could be up to 25 per cent in some cases for workers in agriculture, transport, construction, manufacturing and tourism across Europe. Economic productivity will drop not only in parts of the world already experiencing extreme heat – such as southern Europe, the Middle East and the southern states of the US – but also in countries and companies in northern Europe, which could see big drops in economic output.

Recent results from time and motion studies looking at agriculture in Cyprus showed that the working hours of labourers in the sector dropped by 25 per cent when temperatures reached 35°C when compared to temperatures of 25°C or less. Increasing temperatures also led to more work-related accidents. The researcher say that previous estimates suggesting that rising global temperatures will result in declines in overall global productivity of between one and two per cent were too conservative.

Rising temperatures have been blamed for an increase in mortality rates among foreign workers involved in construction projects in the Gulf state of Qatar.

A 2016 study by scientists at Germany’s Max Planck Institute concluded that across much of the Middle East and North Africa levels of intense heat will make any outdoor work virtually impossible by mid-century, CNW reports.

Compiled by Reinhold Pape


Nature Climate Change, 26 October 2015

Climate News Network, 4 September 2017


In this issue