SINGAPORE - The world marked its first Earth Day in 1970 - and pretty much every year since then, the planet was in worse shape than the year before.

This year, as nations try to recover from the pandemic, looks to be no exception.

The rapid growth of economies and the human population in the past five decades has severely stretched the planet's resources. Nature's piggy bank has been raided repeatedly, its riches plundered, leading to widespread pollution, degradation of ecosystems and an alarming spike in the extinction of species.

The little blue-green orb in space isn't in great shape.

In 1970, humanity was largely in balance with nature, with our annual resource demand matching what nature could replenish.

By 2020, we needed 1.6 earths to meet our needs and on Aug 22, we marked World Overshoot Day. This is "the date when humanity's demand for ecological resources and services in a given year exceeds what Earth can regenerate in that year", according to overshootday.org.

There are glimmers of hope.

The pandemic has reminded many of the value - and fragility - of nature. Parks, green walks and just getting outside have been a key part of people's routines.

Sweeping lockdowns at the start of the pandemic also literally cleared the air and quietened the seas. Nature came back to life and crept into our lives.

Many people now want less polluting transport, more cycling paths, cleaner air and economic recovery funding more focused on green financing, renewable energy and electrification of transport.

A green recovery is widely regarded as a good opportunity to ramp up the fight against climate change, help the environment and create new jobs, too.

Many also saw the link between ecological destruction and the pandemic - that the large-scale clearing of forests puts us more at risk of being exposed to dangerous viruses and other organisms, especially when linked to the wildlife trade.

But as valuable as this all is, the world really has to make major changes in the way it produces and uses energy, grows its food and manages its waste. It must halt the destruction of forests, wetlands and grasslands and the plundering of the seas.

A key step is putting a price on nature, truly valuing the benefits, or ecosystem services in technical-speak. Without nature, there is no oxygen or soil to grow our food, no water for rivers to fill our dams with, or insects to pollinate our crops. In 2018, WWF estimated the value of ecosystem services to humanity at US$125 trillion (S$166 trillion) a year.

In 2019, a landmark assessment of life on earth said nature is declining at an unprecedented rate and the pace of extinction of plants and animals is accelerating, with up to a million species at risk of being lost.

The report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services said mankind needs to make urgent and sweeping changes to economies and the way goods are produced and consumed to stem the rapid decline of nature.

In another assessment, WWF's global Living Planet Index 2020 showed an average 68 per cent fall in monitored populations of mammals, birds, amphibians, reptiles and fish between 1970 and 2016.

Climate change remains the single gravest threat to humanity and nature. Rising temperatures and higher sea levels are already proving deadly and destructive and unless greenhouse gas emissions are cut rapidly and deeply, the impacts will only prove more costly in terms of lives and economic damage.

For example, an estimated 710 million children live in the 45 countries that are at the highest risk of suffering the impacts of climate change, a study by Save the Children released on Monday (April 19) said.

More than 193 million of these children live in Asia and the Pacific, which is home to seven of the highest-risk countries.

Children in these countries will, for example, be affected by food shortages, diseases and other health threats, and water scarcity, or be at risk from rising water levels - or a combination of these factors, the study says.

Which makes this year's Earth Day so vital.

US President Joe Biden's Earth Day climate summit starting on Thursday (April 22) aims to reset global climate diplomacy and galvanise stronger action ahead of the UN's COP26 climate meeting in November. If he succeeds, there is hope that the risks from the climate and biodiversity crises can be reduced.

Ultimately, both are man-made crises and we can do something about them. There are a growing number of solutions to green our economies, be more efficient in our use of resources and greatly improve waste management.

A great global green transition, if well-managed and carried out equitably, is possible, vital and need not cost the earth.