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World Environment Day 2020: A wake-up call

“The foods we eat, the air we breathe, the water we drink and the climate that makes our planet habitable all come from nature.

Yet, these are exceptional times in which nature is sending us a message:

To care for ourselves we must care for nature.

It’s time to wake up. To take notice. To raise our voices.

It’s time to build back better for People and Planet.

This World Environment Day, it’s Time for Nature.” [1]


On World Environment Day, it is time to reflect on how we are tracking, individually and as a species.  Homo sapiens literally means wise man. We could well ask – ‘when did we become so stupid?’

Many clinical years working in intensive care taught me that we want to live. Our loved ones want us to live and to flourish. As individuals, we all want to live free and fulfilling lives, unencumbered by poor health. Yet it appears that collectively we don’t really care if we continue to exist at all. It is an anathema.

The ancients [2] understood the relationship between good health, clean food, clean air and clean water. Humanity flourished during the Holocene’s congenial climate. We secured food supplies through the development of agriculture and animal husbandry. We discovered ingenious ways to channel water to ever growing towns and cities, and we knew the imperative and mastered the art of removing waste material. Indeed, public health laws and epidemiology emerged from failures to abide these basic tenets of securing clean water supplies during the industrial revolution. We re-learned the lessons, and again flourished.

Yet somewhere along the line, we have again forgotten the importance of maintaining a healthy environment. Post World War II, a surge in industrialised effort drove the Great Acceleration in resource extraction and associated lifestyle improvements. Global population exploded, driving ever higher needs for resource materials, land, and water use and an insatiable desire for MORE.

Deemed insignificant, waste generation was managed by the misguided mantra “the solution to pollution is dilution”. It seemed inconceivable that dumping in the vast oceans could be problematic. Burning fossils fuels into the atmosphere was thought similarly limitless. The entire planet, and all her rich bounties were there for the plunder, for profiteering without thought of consequences or limitations, or ethical notions of leaving some for future generations.

So where does humanity stand on World Environment Day 2020? The short answer is, well on track for our collective demise.

Despite the scientific understanding of the  physical laws of nature, despite the growing evidence in the scientific literature, testimonies of the scientists and reports from leading groups such as the United Nations, the IPCC, WHO, and even the economic groups of the World Bank and World Economic Forum, the world politic is reluctant to change course and save itself.

We know we are on the path to ruin. We have been told. But we prefer not to listen. Hence the anathema. The technology exists to decarbonise the world’s economy and create green employment options. Water wise technologies exist, and we can feed the world with less animal fat and associated cardiovascular risk. A healthy future is possible, but we must ACT to secure it.

Here is the state of play June 5, 2020.

Global warming is accelerating. The science underpinning the greenhouse effect has been known for over 200 years, yet despite numerous IPCC reports, greenhouse gas emissions have risen 1.5% per year, and are rising about 100 times faster than previous natural increases, such as the end of the last ice age 11,000-17,000 years ago. Global meteorological records confirm that all of the 10 warmest years have occurred since 2005, and 2019 was the second warmest year in the 140-year record. To date, 2020 is tracking as the second hottest year on record, surpassing last year.

Translating this into health and wellbeing brings depressing news. There is an upper limit to human thermotolerance. Heat exposure kills more people than all other natural disasters combined. Around 30% of the world’s population are currently exposed to deadly heat for at least 20 days a year, and if current levels of emissions persist, this figure will rise to 74% by 2100.

Droughts are increasing in frequency, 2.2 billion people lack access to clean water, and 4.2 billion people lack access to sanitation. Cape Town, a city of 4 million people suffered a multiyear drought, and became perilously close to having its taps turned off. As in other countries, it is no longer uncommon for Australian towns to reach Day Zero, running out of water brings wide ranging physical and mental health problems. Poorer countries suffer more.

Heat and drought trigger fires. Humanity is causing the sixth mass extinction.

Rising sea levels directly threaten the homes for 680 million people living in low-lying coastal zones (nearly 10% of the 2010 global population), and projected to reach more than one billion by 2050. Coastal retreat is being planned, but how many will be able to move, and where will they go?

The search for food sources has stressed the natural environment. Overcrowding and high-density living present a catalyst for disease transmission. Today, we witness a global pandemic triggered by human-environment interaction gone wrong which has upended economic stability.

To survive, we MUST care for nature, so that nature can care for us.

Liz Hanna PhD, MPH, BA, FPHAA, FACN chairs the Environmental Health Working Group of the World Federation of Public Health Associations, and is immediate past President of the Climate and Health Alliance. At the Australian National University she Convened Australian National Climate Change Adaptation Network for Human Health and directed the “Working in the Heat” research program. You can follow her on Twitter @_LizHanna


  2. McMichael A. Climate Change and the Health of Nations. Oxford University Press; 2017. 392 pp.

Featured Image by Kalman Kovats from Pixabay

  1. I am happy to read this blog and you have written about World Environment day. Nowadays chemicals and the smoke of vehicles pollute the air. Thanks for writing this amazing blog.

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