The age of the humans
Scientists’ report expresses alarm at devastating effect on the planet of our activities, writes Sheree Bega
THE changes humans have wrought on the planet in recent decades have been on such a scale they have altered it beyond anything it has experienced in its 4.5 billion year history.
“Our influence is so profound it is pushing the planet into a new age that geologists are calling the Anthropocene: the Age of Humans,” stated a new report, Our Future on Earth 2020, released last week in South Africa.
In the Anthropocene, humanity has become a “geophysical force on a par with the earth-shattering asteroids and planet-cloaking volcanoes” that defined past eras.
The 53-page report, produced by Future Earth, a global network of scientists, researchers and innovators, provides “a snapshot of our world at the start of 2020, helping to make sense of the state of this unique biophysical-human ecosystem we inhabit as a planetary-changing species”.
Millions of years from now a stripe in the accumulated layers of rock on earth’s surface “will reveal our human fingerprint just as we can see evidence of dinosaurs in rocks of the Jurassic, or the explosion of life that marks the Cambrian”.
The influence of humans will show up as changes in the chemistry of the oceans, the loss of forests and the growth of deserts, the damming of rivers and the retreat of glaciers.
“The fossil records will show the extinctions of various animals (happening at 1 000 times the historic rate) the chemical fingerprint of materials such as plastic carrier bags and the physical footprint of projects like the oil sands mines of Alberta, Canada, which annually move twice as much earth than flows down all the rivers in the world in a given year,” the report claims.
Today, earth is a human planet, said the report.
“We are now the most numerous big animal on earth and the next in line are the animals we have created through breeding to feed and serve us. Four-tenths of the planet’s land surface is used to grow food. Three-quarters of the world’s fresh water is controlled by us. Some 75% of the globe’s terrestrial ecology has been significantly modified by humans.”
While earth has been improved for human survival in a number of ways, the report suggests “we have also made it worse: using up its resources, killing off its biodiversity, polluting it with waste and straining its capacity to support us”.
Some of this can be overcome through technological advances, migration, or other adaptations. “Others we will need to reverse. Some others we will need to learn to live with.”
“We live in an era where it is declared that humans are one of the biggest forces on earth, as opposed to the planet’s natural forces such as tectonics, volcanism and ocean processes,” said Professor Bob Scholes, of Wits University’s Global Change Institute, who sat on the report’s editorial board.
“We are heading for a future with a 3.5ºc increase in global temperatures, where the Paris Accord was trying to limit the rise to 2ºc. We are not getting close to that.
“One of the key challenges of our time is trying to find ways to navigate our way into the future in just and sustainable ways. The Sustainable Development Goals, the climate and disaster risk reductions challenges facing us, all require purposeful considerations of how we live.”
His colleague, Professor Coleen Vogel, of the Global Change Institute, who co-authored an article in the report, said transformations would be required “including how we design and do business and think about our economic future, how we feed ourselves and how we consider, design and construct our livelihoods, homes and how we think about the meaning of work and design workplaces”.
Humanity, she said, needed to think about how it related to nature. “Transformations of how we can align our everyday realities and future change will need to be balanced with what the planet can sustain and will ultimately require personal and systems wide transformations.”
The report seeks to tackle the problems that society is facing, spanning climate, politics and political economy, the deep ocean, forced migration, fake news, biodiversity, food and transformation, with an attempt to find a sustainable way forward to humanity’s future.
It includes the results of a novel, quantitative survey of more than 200 scientists who identified the five main risks most likely to interact and combine into a global systemic crisis.
These are the failure of climate change mitigation and adaptation, extreme weather events, major biodiversity loss and ecosystem collapse, food crises and water crises.
“There are well known connections between the top five identified risks. Many extreme weather events have been clearly attributed to climate change and climate change is making such events more frequent and intense. In some cases extreme weather events exacerbate climate change by triggering the release of carbon stored in terrestrial ecosystems.
“Extreme weather events such as heatwaves or droughts impact crop production and water availability.”
Richard Calland, a constitutional law professor from UCT, who contributed to the report, wrote how climate change denialism was a thread that ran through many of the new right-wing nationalist and populist forces, “of which US president Donald Trump is the most conspicuous example”, but at the same time there was a rise of countervailing voices, especially in grassroots movements.
Odirilwe Selomane, the director of the programme on ecosystem change at Stellenbosch University, also contributed, and said around the world biological systems were becoming more similar to each other, whether those ecosystems are managed by humans or not.
“These profound changes to the fabric of life have considerable impacts on human well-being. Ecosystems provide us with resources for fuel, medicine, food and clean water, all of which depend on complex, biodiverse systems for their healthy maintenance.”
There is a 75% decline in insect abundance, including pollinators while the soil used to grow food has declined in organic content by as much as 15%.
Selomane and his co-authors said addressing the challenges linked to a deteriorating web of life and the consequences for human well-being required urgent action that tackled the root causes of environmental decline.
“The traditional approaches to conservation are unlikely to work by themselves: creating an isolated protected area, for example, or working to conserve one single species, may ignore the complex interrelations between ecosystems and social patterns across huge scales.”
In the oceans, “plastic pollution has captured the world’s attention. Mining of the international seabed is about to become a reality. Fish wars lurk on the horizon”, the report stated.
There is no clear single dietbest for people and the planet, according to the study, which said the recent controversial “planetary health diet”, high in plants, wholegrains and low in animal products and processed foods, would “improve public health, although it would require substantial and perhaps sometimes unrealistic changes to current dietary patterns”.
“There is a clear and urgent need to better understand the trade-offs among nutrition, social, environmental and economic outcomes of our food system.” The report said humanity is “a vast global population facing unprecedented environmental challenges, yet we still have the time and the capability to prevent extreme outcomes, such as runaway climate change and wildlife extinctions”.
Our influence is so profound it is pushing us into a new age
Our Future on Earth 2020
NEW REPORT RELEASED LAST WEEK