Why the world is losing against climate change

This assessment by the Intergovernmental Panel on Climate Change on the current status of climate change indicates that poor and vulnerable people are most at risk of suffering from the impact of global warming in the near and medium terms, as weather extremes have reduced food and water security.

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Human-induced climate change, including more frequent and extreme weather events, has caused widespread adverse effects and related losses and damage to nature and people, beyond natural climate variability. Some development and adaptation efforts have reduced vulnerability; however, across sectors and regions, the most vulnerable people and systems have been observed to be disproportionately affected. The increase in weather and climate extremes has led to a number of irreversible impacts, as natural and human systems have been pushed beyond their ability to adapt.

Climate change has caused substantial damage, and increasingly irreversible losses, in terrestrial, freshwater, coastal and open-ocean marine ecosystems. The extent and magnitude of climate change impacts are larger than was estimated in previous assessments. In addition to widespread deterioration of ecosystem structure and function, resilience and natural adaptive capacity, there have been shifts in seasonal timing due to climate change, with adverse socio-economic consequences. Approximately half of the species assessed globally have shifted polewards; on land, they have also moved to higher elevations. There have also been hundreds of local losses of species due to increases in the magnitude of heat extremes, mass mortality events on land and in the ocean, and loss of kelp forests. Some losses are already irreversible, such as the first species extinctions driven by climate change.

Climate change, including increases in frequency and intensity of extremes, has reduced food and water security. Although overall agricultural productivity has increased, climate change has slowed this growth worldwide over the past 50 years. Ocean warming and ocean acidification have adversely affected food production from shellfish aquaculture and fisheries in some oceanic regions.