The report Global Futures: Modelling the global economic impacts of environmental change to support policy-making, by an Global Futures initiative, which is promoted by WWF, Global Trade Analysis Project (GTAP) and Natural Capital Project, considers the benefits that nature provides to all nations and industries through ecosystem services – such as the pollination of crops, protection of coasts from flooding and erosion, supply of water, timber production, marine fisheries and carbon storage-. The analysis then assesses how the natural assets that provide these services (such as forests, wetlands, coral reefs and fish stocks) would change under various future development scenarios and, in turn, how the consequent changes in ecosystem service supply would affect economic outcomes (including GDP, trade, production and commodity prices).
The results show that in a ‘Business-as-Usual’ (BAU) scenario, “reduced supply of these six ecosystem services alone would lead to a drop of 0.67% in annual global GDP by 2050 (compared to a baseline scenario in which there is no change in ecosystem services by 2050). This would be equivalent to an annual loss of US$ 479 billion compared to the baseline scenario, assuming an economy of the same size/structure as in 2011 (the latest version of the GTAP database and base year for this analysis). Over the period between 2011 and 2050, the total cumulative loss would be US$ 9.87 trillion (3% discount rate).”
According to the authors of the document, “figures are highly conservative and should not be considered an assessment of the total costs of nature’s loss for several important reasons. The current model only considers six of the many ecosystem services provided by nature (those for which there is enough evidence to quantify). Nor does it account for the potential effects of ‘tipping points’ – thresholds beyond which habitats change rapidly and irreversibly, such as rainforests shifting to drier and more fire and drought-prone savannahs, making them vulnerable to catastrophic failure of ecosystem services. As future versions of the model address these issues, it is expected that the economic case will be further strengthened.”