As global leaders gather in Dubai for the 28th Conference of the Parties (COP28) to address the pressing climate crisis, the fate of Earth’s rich biodiversity hangs in the balance. With our planet having warmed by approximately 1.2°C since the pre-industrial era, the discussion revolves around mitigating further temperature increases and safeguarding the diverse ecosystems that span from mountaintops to ocean depths.
Recent research, shedding light on the intricate dance between climate change and biodiversity, suggests that the risks facing wildlife may accelerate with each passing year. The study, which examined the expansion of areas where species face dangerous temperatures, unveils a sobering reality for Earth’s ecosystems.
Overlaying climate model projections with data encompassing over 35,000 species on land and in the ocean, researchers discovered a troubling trend. While many populations may seem secure initially, the area over which each species is exposed to intolerable temperatures is predicted to undergo a sudden and significant expansion in the coming decades.
The study reveals that as global warming intensifies, a considerable portion of populations, previously deemed safe, could swiftly find themselves facing perilous conditions. Startlingly, more than half of the populations within a species projected to be at risk this century could transition from relative safety to facing dangerous heat within a mere decade.
This phenomenon mirrors the alarming situation unfolding on coral reefs. Once infrequent, coral bleaching events caused by extreme sea surface temperatures have become routine, degrading reefs globally on an almost annual basis.
The abrupt escalation of risk portrayed in the research is attributed not only to the rapid pace of global warming but also to the planet’s unique geographical features. The study identifies that thermal thresholds are sharpened by the planet’s shape, where similar temperatures across vast regions can simultaneously expose multiple populations of a species to intolerable conditions.
The implications of this research for COP28 are profound. While the models project where and when species may be exposed to unsuitable conditions, they don’t predict extinction. However, they do suggest that rather than a gradual decline, climate change could trigger sudden collapses in populations and the ecosystems they sustain.
This poses a formidable challenge for conservation efforts, emphasizing the need for advanced threat assessments and early warning systems. Accurately predicting when and where dangerous warming thresholds will be crossed for various species and regions becomes imperative in light of these findings.
The research also underscores the variability in thermal thresholds among different species. While each species has its threshold, the level of global warming at which this occurs varies. Limiting global warming to 1.5°C, as per the 2015 Paris Agreement, would expose 15% of species to the risk of losing at least one-third of their current geographic range. This risk doubles to 30% under the current trajectory of 2.5°C of warming.
Critically, the study contends that there is no safe level of warming for Earth’s biodiversity. The 2°C limit often cited is debunked, with every fraction of a degree of warming holding significance in limiting the loss and damage to biodiversity.
In a stark warning, the researchers caution against complacency, asserting that burying our heads in the sand will not alter the hard biophysical limits governing life on Earth. With the rapid pace of climate change outstripping the adaptive capacity of most species, urgent and decisive action becomes imperative to avert the impending collapse of ecosystems and the societies intertwined with them.
As COP28 deliberates on global commitments and strategies, the urgency to address the intertwined challenges of climate change and biodiversity loss has never been more apparent. The fate of Earth’s dazzling variety of life hangs precariously in the balance, and the decisions made in Dubai may shape the future of our planet for generations to come.
