Credit: IPBES

Climate change and biodiversity loss “mutually” reinforce

The world’s leading scientists have come to terms with the interplay between climate change and biodiversity loss, and suggested more synergies of solutions for both issues at once

As the world has been encountering the great pandemic of Covid-19, which has at the same time exposed critical environmental challenges, over 50 invited leading climate and biodiversity scientists have gathered at the IPBES and the IPCC sponsored workshop to try to address the challenges before coming to terms with the interrelation between climate change and biodiversity loss.

As concluded in their workshop report, Biodiversity and Climate Change, biodiversity loss and climate change are both driven by human economic activities and mutually reinforce each other. Unprecedented changes in climate and biodiversity have combined and increasingly threaten nature and human and their livelihoods and well-being around the world, they said, while underlining that neither will be successfully resolved unless both are tackled together.

“Human-caused climate change is increasingly threatening nature and its contributions to people, including its ability to help mitigate climate change. The warmer the world gets, the less food, drinking water and other key contributions nature can make to our lives, in many regions. Changes in biodiversity, in turn, affect climate, especially through impacts on nitrogen, carbon, and water cycles,” said Prof. Hans-Otto Pörtner, co-chair of the Scientific Steering Committee.

The scientists insisted during the press briefing ahead of the launch of the report yesterday that the discourse was new because previously the two issues were generally addressed separately. So were their solutions, and this can be observed from previous policies, which have largely tackled the issues independently of each other. This time individual pieces of information and knowledge are brought together in one coherent package so that people and policymakers can understand this double message and the relationship between the two challenges, the scientists pointed.

The scientists suggested that addressing the synergies between mitigating biodiversity loss and climate change while considering their social impacts offers the opportunity to maximize benefits and meet global development goals.

Prof. Pörtner said a sustainable global future for people and nature is still achievable, but it requires transformative change with rapid and far-reaching actions never before attempted on ambitious emissions reductions.

In addition, a profound collective shift of individual and shared values concerning nature such as moving away from the economic progress based solely on GDP growth, to one that balances human development with multiple values of nature for a good quality of life could help lessen impacts from unavoidable trade-offs between climate and biodiversity, he added.

“It may be impossible to achieve win-win synergies, or even manage the trade-offs between climate and biodiversity actions in every single patch of a landscape or seascape.

“But achieving sustainable outcomes becomes progressively easier when integrating a mix of actions at larger spatial scales, through cross-border collaboration and joint consultative spatial planning, which is why it is important to also address the lack of effective governance systems and mechanisms to improve integration between solutions for climate change and biodiversity,” the professor also pointed.

Among the most important available actions identified in the report are;

* Stopping the loss and degradation of carbon- and species-rich ecosystems on land and in the ocean, especially forests, wetlands, peatlands, grasslands and savannahs, mangroves, salt marshes, kelp forests and seagrass meadows, as well as deep water and polar blue carbon habitats. Reducing deforestation and forest degradation can contribute to lowering greenhouse gas emissions, by a wide range from 0.4-5.8 gigatonnes of carbon dioxide equivalent every year, the report notes.

* Restoring carbon- and species-rich ecosystems. The scientists pointed to evidence that restoration is among the cheapest and quickest nature-based climate mitigation measures to implement, offering much-needed habitat for plants and animals, thus enhancing the resilience of biodiversity in the face of climate change with many other benefits such as flood regulation, coastal protection, enhanced water quality, reduced soil erosion and ensuring pollination. Ecosystem restoration can also create jobs and income, especially when taking into consideration the needs and access rights of indigenous peoples and local communities, they pointed.

* Enhancing and better-targeting conservation actions, coordinated with and supported by strong climate adaptation and innovation. The scientists said protected areas currently represent about 15% of land and 7.5% of the ocean. Positive outcomes are expected from substantially increasing intact and effectively protected areas. Global estimates of exact requirements for effectively protected and conserved areas to ensure a habitable climate, self-sustaining biodiversity, and good quality of life are not yet well established but range from 30 to 50 per cent of all ocean and land surface areas.

Options to improve the positive impacts of protected areas include greater resourcing, better management and enforcement, and improved distribution with increased interconnectivity between these areas, the scientists pointed. Conservation measures beyond protected areas are also spotlighted, including migration corridors and planning for shifting climates, as well as better integration of people with nature to assure equity of access and use of nature’s contributions to people.

* Increasing sustainable agricultural and forestry practices to improve the capacity to adapt to climate change, enhance biodiversity, increase carbon storage and reduce emissions. These include measures such as diversification of planted crop and forest species, agroforestry, and agroecology. Improved management of cropland and grazing systems, such as soil conservation and the reduction of fertilizer use, is jointly estimated by the report to offer annual climate change mitigation potential of 3-6 gigatonnes of carbon dioxide equivalent.

* Eliminating subsidies that support local and national activities harmful to biodiversity such as deforestation, over-fertilization, and over-fishing can also support climate change mitigation and adaptation, together with changing individual consumption patterns, reducing loss and waste, and shifting diets, especially in rich countries, toward more plant-based options.

Some climate mitigation and adaptation measures identified by the report as harmful to biodiversity and nature’s contributions to people include planting bioenergy crops in monocultures over a very large share of land areas, planting trees in ecosystems that have not historically been forests and reforestation with monocultures, especially with exotic tree species, and increasing irrigation capacity.

Any measures that focus too narrowly on climate change mitigation should be evaluated in terms of their overall benefits and risks. The same applies to some technical measures too narrowly focused on adaptation, such as building dams and sea walls, the scientists recommended.

“Land and ocean are already doing a lot, absorbing almost 50% of CO2 from human emissions, but nature cannot do everything.

“Transformative change in all parts of society and our economy is needed to stabilize our climate, stop biodiversity loss and chart a path to the sustainable future we want. This will also require us to address both crises together, in complementary ways,” said Ana María Hernández Salgar, Chair of IPBES.

Source: IPBES