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human activity and the destruction of the planet


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The effects of heat waves on human survivability

An article in the New Scientist (No.3161) by John Pickrell, entitled “Too hot to handle”, discusses the increasing trend of heatwaves throughout the world, as a result of climate change.

heatwave

Pickrell starts by discussing Australia, which had a heatwave in January 2017, with the hottest ever recorded temperatures in Sydney and Brisbane (Sydney had over 47 degrees). Large parts of the country had temperatures over 40 degrees C for weeks on end, as well as bush fires.  Many of the unique species of wildlife common to Australia had to be rescued from fires and heat, many of them suffering from heat exhaustion, burns, dehydration and stress.

koala

kangaroo

 

Temperatures of 50 degrees C are predicted by 2040 for Australia.

Pickrell then goes on to cite papers, which give statistics about fatalities during heatwaves, one from The Lancet which covered research by 26 institutions (including the World Health Organization).

The 2003 heatwave in France killed 70,000 people – but it would appear that the level of humidity is the crucial factor, as high levels of water in the atmosphere can reduce the body’s ability to cool down through sweating.  To sweat effectively, you must maintain your blood volume, so dehydration can cause heat stress, followed by heat stroke, multiple organ failure and possible death.  The elderly and children are at greater risk of heat stroke, as well as those on medication or with heart disease.

I came across another wordpress website, which gives a useful chart showing temperature against relative humidity and which combinations are lethal:

See: https://andthentheresphysics.wordpress.com/2017/06/24/heatwaves/

and below for the table (with acknowledgments):

nclimate_heatwaves

The black crosses in the chart above show temperature and relative humidity during events that were lethal. The blue line shows the likely boundary between lethal and non-lethal events, and the red line is a 95% probability threshold.


According to The Lancet, global warming has reduced the workforce in India by 418,000.


An interesting map of the world is given in the New Scientist article to show the probability of deadly heatwaves for three global warming scenarios: 1.5 degrees C; 2 degrees C and 4 degrees C.  This can be seen by clicking on the link below:

heatwaves data

It shows that, even with an increase in global temperature of 2 degrees, many parts of the world will become uninhabitable, through rising temperatures: North West Africa, much of the Middle East, parts of Central and South America, India, Pakistan and Bangladesh and much of Australia.  At four degrees the situation is dire throughout much of the tropical world.

The New Scientist article concludes with a list of advice on how to keep cool.


 Another academic article on a similar subject has been published in the Proceedings of the National Academy of Science USA by Sherwood and Huber in 2010 (Vol 107, (21), 9552-5) entitled “An adaptability limit to climate change due to heat stress.”  This article has been summarised in the Science & Technology section of the The Observer (10th Sept. 2017).  This article gives a chart showing which species die at particular degrees of warming above pre-industrial levels.  Amphibians will be the first to go (at 0.6 degrees+), followed by penguins, due to loss of food sources, as the krill populations dwindle. At 1.6 degrees+, the wooded tundra is lost, along with its inhabitants, moose, lynx and brown bears, followed by large African mammals, such as elephants, then rain forest dwellers (orangutans, jaguars, sloths) at 2.6 degrees+.  At a warming of 4 degrees, 70% of species would be extinct, coral reefs dead and deserts would expand across the world. The fate of humankind would be dominated by mass migration, on a scale even larger than we see today, with water resources extremely limited, as we would have to abandon most of the Earth or live underground.  The authors predict that, by 2050, temperatures will be in a range that nobody has experienced before.

It is interesting to note that the Australian town of Coober Pedy, a major site for opal mining, has already built an underground town, including hotels, for those times in the year when it is already too hot to live above ground.


2nd August 2018

Since this post was first written, time has now moved on into 2018 with heatwaves across much of the northern hemisphere (see other posts on this site for details).  Even climate sceptics are now beginning to accept that climate change is with us, with the extremes of weather which accompany it.

A piece this week in The Guardian by David Carrington deals with the issue of human survivability during heat waves.  I quote a short passage from him, in which he summarises scientific work on the issue:

The new analysis assesses the impact of climate change on the deadly combination of heat and humidity, which is measured as the “wet bulb” temperature (WBT). Once the WBT reaches 35C, the air is so hot and humid that the human body cannot cool itself by sweating and even fit people sitting in the shade die within six hours.

A WBT above 31C is classed by the US National Weather Service as “extreme danger”, with its warning stating: “If you don’t take precautions immediately, you may become seriously ill or even die.”

He then goes on to discuss which parts of the world are most at risk of high WBT temperatures.  This would appear to be the north China plain, with a population of 400 million people, most of them farmers.  The scientists who produced the data have predicted that by 2070 to 2100, this area of the world will become uninhabitable.  Other areas at risk are the Middle East, around the Gulf (particularly Dubai, Abu Dhabi, Doha and the coastal cities of Iran) and parts of South Asia (around the Indus and Ganges valleys).

For the full Guardian article, see:

https://www.theguardian.com/environment/2018/jul/31/chinas-most-populous-area-could-be-uninhabitable-by-end-of-century?utm_source=esp&utm_medium=Email&utm_campaign=Green+Light+2016&utm_term=282539&subid=2617869&CMP=EMCENVEML1631



July 2019

The UK has experienced another heatwave period this summer, with record temperatures being reached in a number of countries.  It was particularly humid in the UK, with weather forecasters predicting the humidity above 50%, a level which can prove fatal with temperatures above 25ºC, according to the graph shown above.

So its worth looking again at the relationship between WBT (wet bulb temperature) and death due to heat stress.  The following can be found in Wikipedia:

“Living organisms can survive only within a certain temperature range. When the ambient temperature is excessive, humans and many animals cool themselves below ambient by evaporative cooling (sweat in humans and horses, saliva and water in dogs and other mammals); this helps to prevent potentially fatal hyperthermia due to heat stress. The effectiveness of evaporative cooling depends upon humidity; wet-bulb temperature, or more complex calculated quantities such as Wet Bulb Globe Temperature (WBGT) which also takes account of solar radiation, give a useful indication of the degree of heat stress, and are used by several agencies as the basis for heat stress prevention guidelines.

A sustained wet-bulb temperature exceeding 35 °C (95 °F) is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan; at this temperature our bodies switch from shedding heat to the environment, to gaining heat from it. Thus 35 °C (95 °F) is the threshold beyond which the body is no longer able to adequately cool itself. A study by NOAA from 2013 concluded that heat stress will reduce labour capacity considerably under current emissions scenarios.

A 2010 study concluded that under a worst-case scenario for global warming with temperatures 12 °C (22 °F) higher than 2007, the wet-bulb temperature limit for humans could be exceeded around much of the world in future centuries. A 2015 study concluded that parts of the globe could become uninhabitable. An example of the threshold at which the human body is no longer able to cool itself and begins to overheat is a humidity level of 50% and a high heat of 46 °C (115 °F), as this would indicate a wet-bulb temperature of 35 °C (95 °F).”



 


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The Effects of Climate Change on Human Health

In Chapter 1 of my book (Our beautiful world in harmony), I provide information on how climate change is affecting human health.  This is mainly taken from a 43-page report, ‘A Human Health Perspective on Climate Change’, written by Prof. Anthony Costello and others in 2010 . A full citation of the source can be found as reference 12 in the list of references given on this website.

Now, a new multi-author report, published in the Lancet, gives further supporting evidence.   It is entitled The Lancet Countdown of Health and Climate Change: from 25 years of inaction to a global transformation on public health.

http://thelancet.com/pdfs/journals/lancet/PIIS0140-6736(17)32464-9.pdf

The Lancet Countdown tracks progress on health and climate change and provides an independent assessment of the health effects of climate change, the implementation of the Paris Agreement,1 and the health implications of these actions. It follows on from the work of the 2015 Lancet Commission on Health and Climate Change, which concluded that anthropogenic climate change threatens to undermine the past 50 years of gains in public health, and conversely, that a comprehensive response to climate change could be “the greatest global health opportunity of the 21st century”.

This article is available free of charge.

Some of its findings:

  1. Health Effects of Heat Waves

Statistical evidence is provided to show that 125 million more vulnerable people over the age of 65 years were exposed to heatwaves in 2016 compared with 2000.

2. Labour Capacity and Heat stress

“Extreme heat causes heat stress and heat stroke, exacerbations of pre-existing heart failure and kidney disease.”

Global labour capacity of rural labourers, such as farmers, has fallen by 5·3% from 2000 to 2016 due to rising temperatures and the inability to work when it’s too hot.

3. Infectious Diseases

Due to changing climatic conditions in countries where dengue is endemic, the capacity for one of the main mosquitoes (Aedes aegpyti) to transmit dengue fever has increased globally since 1950 by 9·5%.
4. Air Pollution and Public Health

Poor air quality impacts health by increasing rates of stroke, heart disease, lung cancer, and chronic and acute respiratory diseases.

Air pollution from a range of sources contributed to over 1·9 million premature deaths across southeast Asia in 2015.  A graphic in the report provides the numbers of deaths in 21 South East Asian countries, caused by particular polluting sources.

ADAPTATION,PLANNING AND RESILIENCE:

A particularly severe heatwave in the summer of 2003 resulted in more than 70 000 excess deaths across Western Europe. Health systems were unprepared and quickly overwhelmed.

Proven interventions will help prevent loss of life in the future:

  •   Developing clear heatwave and climate change management strategies and establishing early warning systems.
  •  Mapping vulnerable populations and providing cool-down zones.
  •  Simple engineering solutions, such as ensuring adequate ventilation for hospitals and nursing homes.

COAL PHASE OUT:

Coal is the largest contributor to greenhouse gas emissions of all fossil fuels, causing severe air pollution and affecting human health. While coal use increased globally since 1990, it appears to have peaked in 2013 and is now declining.  A graphic shows this levelling off but also demonstrates that China is still by far the highest user of coal to supply energy.

A growing number of countries have committed to ensuring coal is completely phased out over the next decade:

 

Divestment from fossil fuels

Research on health and climate change
“Science is critical to increasing public and political understanding of the links between climate change and health.
Since 2007, the number of scientific papers on health and climate change has more than trebled.


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Heat waves in UK and US – effects of global warming? What about India? The Middle East? Pakistan? Iran? Portugal? Africa?

June has been really hot here in the UK and there are reports that the USA is experiencing similar high temperatures. In July and August in Europe, temperatures have risen into the 40s, with a heatwave named ‘Lucifer’, and reports that snow is melting in the Italian alps and increased deaths due to heat stroke.

p05bjnl3

 

USA: A report from USA Today has said that due to the heat, American Airlines have had to cancel several flights from Phoenix, as follows:

The extreme heat forecast for Phoenix on Tuesday has caused the cancellation of 20 American Airlines flights out of Sky Harbor International Airport. 

According to a statement from American Airlines, the American Eagle regional flights use the Bombardier CRJ aircraft, which has a maximum operating temperature of 118 degrees. Tuesday’s forecast for Phoenix included a high of 120 degrees, and the flights that are affected were to take off between 3 and 6 p.m. MT.

Customers affected were told to contact American Airlines for rebooking options or to request a refund.

Extreme heat affects a plane’s ability to take off. Hot air is less dense than cold air, and the hotter the temperature, the more speed a plane needs to lift off. A runway might not be long enough to allow a plane to achieve the necessary extra speed. “

Are we to experience more and more of these excessive temperature events? After all, every one of the last three years has been the hottest on record. Will this be enough to change Donald Trump’s mind about the Paris Agreement?

Another report in the Huffington Post on 14th February 2018, cites a study from Princeton University, which predicts that, by 2100 most cities are set to become unbearably warm. Thanks to a combination of impenetrable, concrete surfaces and lack of moisture in the surrounding areas these cities will become hot spots during a heat wave.  By 2050, it is predicted that 70% of the world’s population could be living in cities.

http://www.huffingtonpost.co.uk/entry/by-2100-cities-are-going-to-become-unbearably-warm_uk_5a841b3be4b02b66c513b133?ncid=webmail

In the UK, 2017 was the hottest June since 1976.  I can remember the heat in that year – but somehow it felt like a dryer heat then. Still uncomfortable if you were out in the sun but not quite as sticky and debilitating as this June has been.

And whilst we are feeling the effects here in a temperate country, let us not forget those hotter countries where they are experiencing even higher temperatures than normal. And the devastating forest fires in Portugal, France, the USA and Australia.

IRAN

Iran, having the highest ever recorded temperature in June 2017, with Pakistan not far behind, both well into the 50s Celsius.

18541795550_fe4f65fe75_k

Ahvaz in Iran, which reached the highest ever recorded temperature on 29th June 2017, a staggering 129.2 degrees Fahrenheit

Heat waves are more easily attributable to climate change, according to scientists, because there is a clear connection between carbon absorbed in the atmosphere and temperature rises. Such extreme heat put the residents of Ahvaz in serious danger for dehydration, heat fatigue, heat cramps, heat stroke, and other illnesses. For the elderly, these risks are amplified.

Parts of Iran have also struggled with extreme droughts in recent years, which is threatening the country’s water sources and harming agriculture. Lake Urmia, for instance, once the sixth-largest saline lake in the world, has lost 90% of its water since 1970.  Taken together, Iran is experiencing climate change more intensely than many other countries in the world.

1-s2.0-S0380133014002688-fx1

India

India_heat_wave_large-1-678x381

My book finishes with a quote from Devinder Sharma from India. Here is part of what he wrote in 2016 (and 2017 has been even worse):

It has now become even more obvious than before that the world we are living in has
changed profoundly in the last five years. Every passing year is turning out to be hotter
than the previous. It is just the middle of April but vast tracts of India are reeling under
scorching heat with temperatures zipping past the 40 degrees mark. In 13 States, April
temperature is higher by 8 degrees from the average. This will only intensify, as the
season warms up.  India is on the boil, literally………….

“We are now in mid-April and I can already feel the average temperatures creeping up. While we can survive, my thoughts go out to the 700 million people reeling under two consecutive years of drought. With wells almost dry and walking on a parched land they will now have to confront an unkindly hot sun. Some reports say wells have dried to a level in Marathwada not seen in past 100 years. Another report tells us that 133 rivers have dried in Jharkhand. To make matters worse, a BBC report indicated that the government might pipe Himalayan water and carry it all the way to the parched lands. After all, this is the surest way to add to GDP!

The relatively well-off in the cities, towns and suburbs have the facility to switch on an air conditioner or an air-cooler but imagine the plight of majority population who have no
other option but to survive under shade, be it at home or under the tree.
Water bodies have dried up. Many studies point to a steep fall in water levels in major
reservoirs to the levels that are lowest in a decade.”

Sharma also reports that, in the previous year (2015), there were 1,500 deaths from the effects of heat wave in Andhra Pradesh alone.

Pakistan has also felt the effects of extreme heat.  The photograph below shows people in Lahore cooling off in a water channel.

PAKISTAN-WEATHER

AFRICA

And in Africa, there are more famines and drought and more starving children.  Also, from the following website:

https://newrepublic.com/article/143019/one-meal-day-lake-chad-vanishes-seven-million-people-starvation

came this report:

Not so long ago, Lake Chad was one of the largest bodies of water in Africa. The thick reeds and vital wetlands around its basin provided vast freshwater reserves, breeding grounds for fish, fertile soil for agriculture, and grasslands where farmers grazed their animals. In 1963, it spanned almost 10,000 square miles, an expanse roughly the size of Maryland. But as climate change has taken its toll, the lake has shrunk by 90 percent. Today, only 965 square miles remain. Wetlands have given way to sand dunes. Farmers have abandoned their fields. Those who still live by the lake struggle to survive, beset by chronic drought and the slow onset of ecological catastrophe.”

0281-lakechad-EN_0

Update August 17th 2017

Now today, I have received a report to say that July 2017 has been equal first in being the hottest global temperature since records began.  And yes, it is equal with July 2016!  July is traditionally the hottest month of the year globally and the last two Julys have been the hottest ever.

The researchers from England, France, Switzerland, and the U.S., found that climate change made the intensity and frequency of the extreme heat at least twice as likely to occur in Belgium, at least four times as likely in France, Switzerland, the Netherlands, and central England, and at least 10 times as likely as Portugal and Spain.

The unusual heat was not limited to Europe, either.

On July 21, Shanghai, China, which is the most populated city in the world with 24 million residents, set a record for its hottest day since record-keeping began there in 1872. The high temperature on that day was 105.6 degrees Fahrenheit, or 40.9 degrees Celsius, and it fits with a pattern of hotter weather in that city.

The planet has not had a cooler than average month since December of 1984.

The graph below shows seasonal temperatures from 1884 to 2017.

https-blueprint-api-production.s3.amazonaws.comuploadscardimage5647026012232f-acd6-4098-828f-491dbac30eda

Can we continue to ignore these facts and behave as if nothing is happening?

I believe that we are seeing the beginnings of climate change effects that can only get worse if nothing is done to reverse the trend.