The four horsemen of the apocalypse are destroying planet Earth

Climate change and loss of biodiversity are the terrible twins working together to threaten human existence. Unfortunately, their wicked problems are accompanied by two equally important drivers of calamity —population and economic growth. These four horsemen gallop in unison and must be considered together.

Climate change

After several decades characterized by misinformation and then prevarication on the veracity of climate change, governments are now acceding to the warnings from climate scientists and their learning experience from rapidly increasing extreme weather events. However, their actions remain insufficient to ensure future world temperatures allow civilization to exist. Indeed, we need to arrest greenhouse emissions within the next two decades. 

The positives are that the science is secure, we can measure our success and failure by measuring atmospheric carbon dioxide and methane, and we have the option of spending hundreds of billions of dollars to suck these gases out of the atmosphere if all else fails.

However, much climate change mitigation is based on technological fixes, some of which are problematic and many indeed create their own environmental harms. 

Biodiversity and its ecological services

Climate change and biodiversity crises impact each other. Climate change is a significant cause of biodiversity loss, but even if climate change was contained today, the biodiversity crisis would still proceed, although more slowly, for its fundamental cause is the consumption of the natural environment for economic gain by a population too large for the world’s finite natural resources.

The 2019 “Warning of a Climate Emergency,” signed by over 11,000 scientists, identified continued increases in human population and the world’s gross domestic product as causes of ecological decline.

The science to explain how the loss of biodiversity and their ecological services will end civilization is poorly understood. It is diffuse, complex and we have no one measure to assess demise or success. There are no dramatic examples such as storm, flood, fire and heat domes by which we experience the consequences. 

Healthy ecosystems, interdependent webs of millions of living organisms and the physical environment they create, are vital to all life on Earth. They are our life support systems that provide clean air, freshwater, fertile soil for food as well as many other resources and medicines. We are part of this web of life but now plunder it beyond repair.

As recognized by scientists from Australia and the U.S., the scale of the threats to all these forms of life — including humanity — is in fact so great that it is difficult to grasp even by well-informed scientists. Awareness by public government and industry is weak which explains the universal presence of ineffective environmental protection and laws.

Some outcomes will relate to failure of agriculture with hunger, starvation and conflict. In the Dust Bowl disaster in the early 1930s, prolonged drought led to the loss of 1.2 billion tons of soil across the Great Plains and there were thousands of refugees as depicted in John Steinbeck’s 1939 novel “The Grapes of Wrath.” 

With an average rainfall of less than 500 mm, stock grazing had been replaced by wheat production and soil stability conferred by native grasses was lost. As with climate change, the deniers will say such episodes have always occurred and dismiss the increasing prevalence of similar disasters which are now occurring around the world. 

There are a few hopeful developments that indicate increasing awareness by governments.

Long overdue collaboration will now occur between the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the Intergovernmental Panel on Climate Change (IPCC).

Natural capital accounting is underway in 90 countries under the UN SEEA system but both the U.S. and Australia have not yet made progress, as detailed in The Hill.

An international Taskforce on Nature-related Financial Disclosures (TNFD) launched last month will develop a framework for corporations and financial institutions to report on nature-related physical and transition risks.

Population growth

Philip Cafaro, professor of philosophy of the School of Global Environmental Sustainability at Colorado State University, notes many studies show that limiting population growth is among the cheapest, most effective means to limit and help societies adapt to climate change. Yet, population growth is taboo in the current debate. One of the main reasons lies with human rights concerns; this needs to be balanced by the right for humanity’s continued existence and indeed many other species some of which we depend upon.

Cafaro also notes that the IPCC’s 2014 report states that, “Globally, economic and population growth continue to be the most important drivers of increases in CO2 emissions from fossil fuel combustion.” This was reiterated by one of the Working Groups from the 2021 IPCC report, yet it was absent from the 3,676-page final report. 

As detailed in The Hill, American couples are having fewer children than in the past but specific population policy is largely absent and population increases intermittently by immigration. By contrast, Australia is encouraging population growth. When introducing the “baby bonus” scheme in 2002, Australian Treasurer Peter Costello promoted the scheme with the encouragement to “have one for mum, one for dad and one for the country.” This philosophy still exists in our huge country despite our rapidly deteriorating environment with increasing impacts of climate change.

Nevertheless, rational views based on science are being advanced in Australia, for example, the discussion paper “Population and Climate Change.”

The consumer economy  

The fourth most terrifying horseman is the obsession with economic growth which fails to acknowledge that our planet and its biological resources are finite. The leaders and representatives of nations at the UN climate summit COP26 together with a huge contingent from the fossil fuel industries were set in their ideology of growth, progress and prosperity. They cannot conceive of economic reform toward an economy to curb consumerism and consequently it was not addressed in the 2021 IPCC report.

Humanity urgently needs and integrated Intergovernmental Panel report- the IPCBPE report

Unfortunately, a fifth horseman of the apocalypse has now arrived from the Russian steppes, but we must not allow war to distract us from our urgent mission to stop the advance of Four. 

David Shearman (AM, Ph.D., FRACP, FRCPE) is a professor of medicine at the University of Adelaide, South Australia and co-founder of Doctors for the Environment Australia. He is co-author of “The Climate Change Challenge and the Failure of Democracy” (2007) commissioned by the Pell Centre for International Relations and Public Policy.