TY - JOUR

T1 - Future of the human climate niche

AU - Xu, Chi

AU - Kohler, Timothy A.

AU - Lenton, Timothy M.

AU - Svenning, Jens Christian

AU - Scheffer, Marten

N1 - Copyright © 2020 the Author(s). Published by PNAS.

PY - 2020/5

Y1 - 2020/5

N2 - All species have an environmental niche, and despite technological advances, humans are unlikely to be an exception. Here, we demonstrate that for millennia, human populations have resided in the same narrow part of the climatic envelope available on the globe, characterized by a major mode around ~11 °C to 15 °C mean annual temperature (MAT). Supporting the fundamental nature of this temperature niche, current production of crops and livestock is largely limited to the same conditions, and the same optimum has been found for agricultural and nonagricultural economic output of countries through analyses of year-to-year variation. We show that in a business-as-usual climate change scenario, the geographical position of this temperature niche is projected to shift more over the coming 50 y than it has moved since 6000 BP. Populations will not simply track the shifting climate, as adaptation in situ may address some of the challenges, and many other factors affect decisions to migrate. Nevertheless, in the absence of migration, one third of the global population is projected to experience a MAT >29 °C currently found in only 0.8% of the Earth's land surface, mostly concentrated in the Sahara. As the potentially most affected regions are among the poorest in the world, where adaptive capacity is low, enhancing human development in those areas should be a priority alongside climate mitigation.

AB - All species have an environmental niche, and despite technological advances, humans are unlikely to be an exception. Here, we demonstrate that for millennia, human populations have resided in the same narrow part of the climatic envelope available on the globe, characterized by a major mode around ~11 °C to 15 °C mean annual temperature (MAT). Supporting the fundamental nature of this temperature niche, current production of crops and livestock is largely limited to the same conditions, and the same optimum has been found for agricultural and nonagricultural economic output of countries through analyses of year-to-year variation. We show that in a business-as-usual climate change scenario, the geographical position of this temperature niche is projected to shift more over the coming 50 y than it has moved since 6000 BP. Populations will not simply track the shifting climate, as adaptation in situ may address some of the challenges, and many other factors affect decisions to migrate. Nevertheless, in the absence of migration, one third of the global population is projected to experience a MAT >29 °C currently found in only 0.8% of the Earth's land surface, mostly concentrated in the Sahara. As the potentially most affected regions are among the poorest in the world, where adaptive capacity is low, enhancing human development in those areas should be a priority alongside climate mitigation.

KW - Climate

KW - Migration

KW - Societies

KW - CONFLICT

KW - HEAT

KW - HUMAN MIGRATION

KW - PERFORMANCE

KW - migration

KW - climate

KW - societies

KW - KEY

KW - Africa, Northern

KW - Temperature

KW - Humans

KW - Data Mining

KW - Animals

KW - Climate Change

KW - Population Density

KW - Agriculture

KW - Livestock

KW - Human Migration

KW - Population Dynamics

UR - http://www.scopus.com/inward/record.url?scp=85085539369&partnerID=8YFLogxK

U2 - 10.1073/pnas.1910114117

DO - 10.1073/pnas.1910114117

M3 - Journal article

C2 - 32366654

AN - SCOPUS:85085539369

VL - 117

SP - 11350

EP - 11355

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 21

ER -