---
title: "World Scientists' Warning to Humanity"
chunk: 2/5
source: "https://en.wikipedia.org/wiki/World_Scientists'_Warning_to_Humanity"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:07:48.834304+00:00"
instance: "kb-cron"
---

== 2022 warning on population ==
In October 2022, Eileen Crist, William J. Ripple, Paul R. Ehrlich, William E. Rees, and Christopher Wolf all contributed to the Scientists' warning on population, published by Science of the Total Environment as "part of the ongoing series of scientists' warning publications," to address the negative impacts of population size and growth on the climate and biodiversity, which they posit "continues to be ignored, sidestepped, or denied." It calls for two actions that, if heeded, will stop population growth before the end of this century. Firstly, the authors issue a global appeal to all adults to have no more than one child as part of the transformative changes needed to mitigate both climate change and biodiversity loss. Secondly, the warning urges policy-makers to "implement population policies with two key female empowerment components," primarily improving education for young women and girls and providing high-quality family-planning services to all. It emphasizes that "the combination of institutional support to plan one's child-bearing choices and educational attainment, including enhanced opportunity for higher education for women, yields immediate fertility declines." It also posits that a sustainable human population, which according to environmental analysts is "one enjoying a modest, equitable middle-class standard of living on a planet retaining its biodiversity and with climate-related adversities minimized," is between 2 and 4 billion people.
The warning also advocates for combatting poverty, patriarchy and overconsumption by the affluent, and calls for a global wealth tax to be levied primarily against "wealthy nations, industries and people who have benefitted the most from humanity's massive-scale historical and contemporary use of fossil fuels" in order to expand "clean sanitation and water availability, food sovereignty, and electrification via renewables." It stresses that poverty alleviation must include the provision of basic public services, in particular healthcare and education.

== Scientists' Warning series ==
Following the publication of the World Scientists' Warning to Humanity (1992) and its update (2017), the Alliance of World Scientists (AWS) encouraged researchers to develop discipline-specific Scientists' Warning papers addressing focused environmental, ecological, and societal risks. These peer-reviewed articles form a recognised Scientists' Warning series, each explicitly framed as a contribution to the broader Warning movement. The AWS maintains an index of these articles on its official website.
Listed in reverse chronological order (most recent first).