The latest report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) has painted a bleak picture about the impact of climate change on biodiversity, human health and well-being.
There will be an irreversible loss of marine biodiversity due to climate change if things continue as they are, it said.
Coral reefs and coastal fisheries which provide food, prevent malnutrition and stunted child growth among other conditions, would be negatively impacted and lost, the Assessment Report on the Interlinkages Among Biodiversity, Water, Food and Health —known as the Nexus Report — noted.
Heat stress and lack of water availability would also affect crop yield, in turn impacting terrestrial food production. This would have consequences on human health and well-being, worsening food insecurity, especially for vulnerable populations.
“Other direct health impacts include extreme weather events such as heatwaves, flooding, droughts and wildfires, and increased dispersal of pathogens and pollutants (such as untreated wastewater, fertilisers, pesticides, sediments and air pollutants) that can be transboundary,” it noted.
About 218 of 375 (58 per cent) known human infectious diseases may worsen due to climate change, according to current trends.
The report noted that the impacts of climate change are already being witnessed. More than 62,000 deaths reported in Europe in 2022 were directly attributable to heat, while over 1,500 deaths in the United States last year were caused by heat, it said.
In Africa between 2011 and 2020, heat-related deaths among children scaled between 12,000 and 19,000.
In the past 50 years, extreme weather, climate- and water-related events have caused nearly 12,000 disasters, leading to 2 million human deaths. Ninety per cent of those were reported from low- and lower-middle-income countries, the report stated.
The total financial costs of these events were estimated to be about $4.3 trillion globally.
About 21 per cent of global carbon dioxide equivalent emissions in 2018 could be attributed to land use change for food production.
It warned the situation is likely to worsen, as risks of exposure from climate change are projected to double in the scenario of global warming levels touching between 1.5 degrees Celsius and 2 degrees Celsius.
The risks will double further between 2 degrees Celsius and 3 degrees Celsius across multiple sectors.
“This presents a growing challenge to biodiversity and the integrity and functioning of ecosystems in terrestrial, freshwater and marine environments. Intensifying climate change will also stress water resources and undermine agricultural productivity and food productivity in food production systems, exacerbate droughts and flooding, cause increased mortality from heat waves and expand the epidemic belt for vector-borne diseases towards higher latitudes and altitudes,” the report said.
It said functioning and resilient ecosystems were crucial for climate change mitigation and adaptation. They could buffer extreme weather events and act as carbon sinks.
“For example, coastal ecosystems contribute to more than 50 per cent of carbon sequestration in the oceans and provide protection from flooding,” the analysis said.
The report observed that the impacts of climate change can interact with other drivers such as land use change, pushing it to tipping points.
The document pointed out that restoring ecosystems could have multiple benefits. Increasing capacity of degraded lands and water could improve the quality of habitat and restore productivity.
For instance, it found that mangrove restoration in Senegal resulted in increased carbon restoration, improved biodiversity and water quality along with water regulation, enhancing food security, livelihoods and reductions in coastal erosion.