The quality of the air we breathe, the food we eat and the water we drink depend directly on the state of our biodiversity, which is now in severe jeopardy. We need a transformational change in our relationship with nature to ensure the sustainable future we want for ourselves and our children.
Largely overshadowed by other concerns in coverage of the recent report by the Intergovernmental Panel on Climate Change (IPCC) was a section on how much better it will be for biodiversity - the essential variety of all life on Earth - if global warming can be held to 1.5 degrees Celsius rather than 2°C above pre-industrial levels.
Based on one modelling study, involving 105,000 species, the IPCC report estimates that 1.5°C of global warming will dramatically alter the world for 8.0 per cent of plants, 4.0 per cent of vertebrates and 6.0 per cent of insects - eliminating more than half of their geographic range.
In a world 2°C warmer, the figures double for plants (16 per cent) and vertebrates (8.0 per cent), and triple for insects (18 per cent). The knock-on effects for people would be severe.
Similarly, forest fires, the spread of invasive species and other biodiversity-related risks to human well-being are substantially lower at 1.5°C relative to 2°C of global warming.
Ocean temperatures and acidity will rise higher, and ocean oxygen levels will drop further, in a 2°C warmer world, leading to irreversible losses of marine and coastal ecosystems, less productive fisheries and aquaculture, less Arctic sea ice and fewer warm water coral reef ecosystems (70 to 90 per cent losses at 1.5°C; more than 99 per cent at 2ºC), with the loss of all the natural benefits that these provide to people around the globe.
One model projects a more than 3 (three) million tonne drop in the world's annual catch of marine fish at 2°C of global warming, twice the loss anticipated at 1.5°C.
It is against this deeply worrying backdrop that member States of the Convention on Biological Diversity (CBD) meets in Sharm El-Sheikh, Egypt from November 17-28 for the UN Biodiversity Conference. A central focus of the meeting will be a move towards a new set of global biodiversity action goals and targets.
The current goals, established in 2010 in Aichi, Japan, expire in 2020, when they are expected to be formally replaced.
Thankfully, we can point to meaningful progress on the protection and conservation of biodiversity over the past 10 years. For example, the annual rate of net forest loss has been halved; global protected areas have increased to 13 per cent of coastal and marine areas and 15 per cent of terrestrial areas (although not all world ecoregions are adequately covered, and most protected areas are not well connected); and the number of plant genetic resources for food and agriculture secured in conservation facilities has risen.
These successes are not, however, nearly enough to halt the ongoing loss of plant and animal diversity on Earth - a fundamental worldwide extinction crisis, deepening every year, and severely aggravated by climate change.
So, what can world policymakers do next?
To make better decisions on biodiversity, we need the best-possible understanding of the problems and the best evidence on which to act. Authoritative expert assessments, such as the IPCC report, and those of the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), the IPCC's counterpart in biodiversity, provide this evidence.
Founded just six years ago, IPBES has already published seven major assessment reports on, for example, pollination and food production; land degradation and restoration; and regional assessments of biodiversity in Africa, Asia and the Pacific, Europe and Central Asia, and the Americas.
IPBES also has a landmark new assessment report in the pipeline, to be released in Paris next May - the first comprehensive global assessment of biodiversity since the Millennium Ecosystem Assessment of 2005 - it will describe the state of biodiversity and ecosystem services around the world.
For almost three years, about 150 experts - including natural and social scientists, and indigenous knowledge holders - from almost 50 countries have contributed to the report, which covers land-based ecosystems, inland waters and the open oceans.
They have evaluated the changes that have occurred over recent decades, a range of possible scenarios through 2050, and the end results to expect from the pursuit of various policy options, including 'business as usual'.
Once published, the IPBES global assessment will inform not just the critical deliberations on the world's post-2020 biodiversity goals and targets, but all policies and actions related to biodiversity for the next decade and beyond - decisions fundamental also to the achievement of the Sustainable Development Goals and the Paris Agreement on climate change.
The choices humanity makes now will profoundly affect the world's biodiversity, which in turn will impact the future economies, livelihoods, food security and quality of life of people everywhere. We must get them right.
Cristiana Pasca Palmer is the Executive Secretary of the Convention on Biological Diversity (CBD), Montreal, and Anne Larigauderie is the Executive Secretary of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), Bonn.
—Inter Press Service