Our climate projections for 2500 show an Earth that is alien to humans

Every few years since 1990 , we have evaluated our progress through the Intergovernmental Panel on Climate Change's (IPCC) scientific assessment reports and related special reports . IPCC reports assess existing research to show us where we are and what we need to do before 2100 to meet our goals, and what could happen if we don't. The recently published United Nations assessment of Nationally Determined Contributions (NDCs) warns that current promises from governments set us up for a very dangerous 2.7 degrees Celsius warming by 2100 : this means unprecedented fires, storms, droughts, floods and heat, and profound land and aquatic ecosystem change.

While some climate projections do look past 2100 , these longer-term projections aren't being factored into mainstream climate adaptation and environmental decision-making today. This is surprising because people born now will only be in their 70s by 2100. What will the world look like for their children and grandchildren? To grasp, plan for and communicate the full spatial and temporal scope of climate impacts under any scenario, even those meeting the Paris Agreement, researchers and policymakers must look well beyond the 2100 horizon.

Current climate future predictions do not go far enough. Credit: Shutterstock Read more

Global mean near-surface air temperature (solid lines) and thermosteric sea level rise (dotted lines) anomalies relative to the 2000-19 mean for the RCP6.0, RCP4.5 and RCP2.6 scenarios. Shaded regions highlight the time horizons of interest and their nominal reference years. The bottom panel shows spatial anomalies relative to 2000-19 mean for the 2100, 2200 and 2500 climates under the three RCPs. Credit: Lyon et al., 2021 Read more

The Amazon: The top image shows a traditional pre-contact Indigenous village (1500 CE) with access to the river and crops planted in the rainforest. The middle image is a present-day landscape. The bottom image, considers the year 2500 and shows a barren landscape and low water level resulting from vegetation decline, with sparse or degraded infrastructure and minimal human activity. Credit: Lyon et al., 2021, CC BY-ND Read more

Midwest U.S.: The top painting is based on pre-colonisation Indigenous cities and communities with buildings and a diverse maize-based agriculture. The second is the same area today, with a grain monoculture and large harvesters. The last image, however, shows agricultural adaptation to a hot and humid subtropical climate, with imagined subtropical agroforestry based on oil palms and arid zone succulents. The crops are tended by AI drones, with a reduced human presence. Credit: Lyon et al., 2021, CC BY-ND Read more

The Indian subcontinent: The top image is a busy agrarian village scene of rice planting, livestock use and social life. The second is a present-day scene showing the mix of traditional rice farming and modern infrastructure present in many areas of the Global South. The bottom image shows a future of heat-adaptive technologies including robotic agriculture and green buildings with minimal human presence due to the need for personal protective equipment. Credit: Lyon et al., 2021 , CC BY-ND Read more