This article was first published by The Conversation. Space.com's Expert voices: Op-Ed and Insights was contributed by the publication.
Christopher Lyon, Postdoctoral researcher at McGill University, Natural Resource Sciences
Alex Dunhill, University of Leeds Research Fellow in Palaeobiology
Andrew P. Beckerman is Professor of Evolutionary Ecology at the University of Sheffield
Ariane Burke, Professor, Anthropology, Universit de Montral
Bethany Allen, PhD student, School of Earth and Environment University of Leeds
Chris Smith, NERC IIASA Collaborative Fellow, University of Leeds
Daniel J. Hill, Lecturer at the School of Earth and Environment University of Leeds
Erin Saupe Associate Professor Palaeobiology University of Oxford
James McKay Manager, Centre for Doctoral Training University of Leeds
Julien Riel-Salvatore, Professor, Anthropology, Universit de Montral
Lindsay C. Stringer Professor Environment and Geography University of York
Rob Marchant, Professor of Tropic Ecology, University of York
Tracy Aze, Associate Professor Earth and Environment, University of Leeds
Many reports that are based on scientific research discuss the long-term effects of climate change, such as the rising levels of greenhouse gases and temperatures. For example, the Paris Agreement requires that we limit global warming to below 2.0 degrees Celsius above preindustrial levels by the end the century.
Since 1990, the Intergovernmental Panel on Climate Change (IPCC), has evaluated our progress using its scientific assessment reports and other special reports. The IPCC reports evaluate existing research to determine where we stand and what we need before 2100 to reach our goals.
According to the United Nations Assessment of Nationally Determined Contributions (NDCs), current government promises could lead to a dangerous 2.7 degree Celsius increase in temperature by 2100. This would mean unprecedented fires, storms droughts floods and heat as well as profound land- and aquatic ecosystem changes.
Although some climate projections look beyond 2100, they are not being considered in mainstream climate adaptation or environmental decision-making. This is not surprising, given that people born today will be in their 70s by 2100. How will their children and grandchildren see the world?
Researchers and policymakers need to look beyond the 2100-horizon in order to grasp, plan, and communicate the full spatial, temporal, and global impact of climate impacts under any scenario.
After 2100
Will the climate stop warming by 2100? What does this mean for humanity now and in the future? These questions are answered in our open-access article published in Global Change Biology.
Global climate model projections were run based on Representative Concentration Pathways. These are "time-dependent projections for atmospheric greenhouse gas (GHG). Our projections modelled low (RCP6.0), medium and high mitigation scenarios (RCP4.5). This corresponds to the "well below 2 degrees Celsius" Paris Agreement goal. These models will be valid until 2500.
To get an idea of what environmental challenges children and their descendants may face in the future, we also created models of vegetation distribution, heat stress, and growing conditions for major crop plants.
Global mean near-surface temperature (solid lines), and thermosteric ocean level rise (dotted line) anomalies relative the 2000-19 mean RCP6.0, RCP4.5, and RCP2.6 scenarios. The shaded regions indicate the nominal reference years and time horizons of particular interest. The bottom panel displays spatial anomalies relative the 2000-19 mean for 2100, 2200, and 2500 climates in the three RCPs. (Image credit: Lyan et al. 2021
Our model showed that the global average temperature keeps rising above 2100 in both RCP4.5 (6.0) and 6.0. These scenarios result in vegetation moving towards the poles and areas suitable for certain crops being reduced. Some areas with a long history of ecosystem and cultural richness, such as the Amazon Basin may become barren.
We also found that heat stress can cause death in areas of tropical high population. These areas could become uninhabitable. Even in high-mitigation situations, sea level continues to rise due to the expansion and mixing of water in warmer oceans.
Our findings, although they are based only on one climate model show that they fall within the range projections from other models and help reveal the potential scale of climate change on longer timescales.
To really portray what a low-mitigation/high-heat world could look like compared to what we've experienced until now, we used our projections and diverse research expertise to inform a series of nine paintings covering a thousand years (1500, 2020, and 2500 CE) in three major regional landscapes (the Amazon, the Midwest United States and the Indian subcontinent). Images for the year 2500 are based on RCP6.0 projections. They include slightly more advanced, but easily recognized versions of current technologies.
Image 1 of 3. (Image credit to Lyon et al, 2021). The Amazon. The top image shows an Indigenous village pre-contact (1500 CE), with access the river and plants in the rainforest. The middle image shows a modern landscape. The bottom image is a view of the year 2500. It shows a deserted landscape with low water levels due to vegetation decline. There are also minimal infrastructures and little human activity. Image 2 of 3. (Image credit Lyon et. al., 2021). Midwest U.S. The top painting depicts pre-colonisation Indigenous communities and buildings, as well as a variety of maize-based agricultural practices. The second image is of the same area today with large harvesters and a monoculture of grain. However, the last image shows agriculture adaptation to a hot, humid subtropical climate. It is based on oil palms, and arid zone succulents. With a lower human presence, the crops are managed by AI drones. Image 3 of 3. (Image credit to Lyon et. al., 2021). The Indian subcontinent. The top image shows a bustling scene in an agrarian village, where rice planting, livestock use, and social life are all taking place. The second image shows a modern scene that illustrates the combination of traditional rice farming with modern infrastructure found in many parts of the Global South. Bottom image depicts a future with heat-adaptive technologies, including robotic agriculture and green building without the need to have people around.
An alien future?
Between 1500 and now, we've seen colonization, the Industrial Revolution, modern identities, institutions, and mass combustion of fossil fuels. We must stop climate warming. The Earth will be affected in 500 years. This will impact our ability to sustain many basic necessities, especially in our culturally and geographically rooted cultures.
Our high-end projections of Earth are alien to us. We have two choices: reduce emissions and adapt to the warming that we can't escape, or consider living on an Earth different from this one.
This article was republished by The Conversation under Creative Commons. You can read the original article.
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