Researchers say too little emphasis has been placed on two of the most effective ways we could be fighting climate change - limiting population growth and social justice.
"Since 1997, there have been more than 200 articles published in Nature and Science on climate mitigation, but just four of those discussed social justice, and only two considered population," said William Ripple, professor of ecology at Oregon State University.
"Clearly social justice and population policy are not getting the attention they deserve in the struggle against the climate emergency."
Dr Ripple and his colleague Christopher Wolf say "curbing population growth in the context of social justice" could "make substantial contributions to climate mitigation and adaptation".
Since 1970, the average global temperature has risen by 0.8C. In that time the world's population has doubled, and emissions of carbon dioxide have more than doubled, data from the International Energy Agency shows.
World Bank figures back that up, showing we're emitting slightly more per capita than a half-century ago.
"More than 11,000 scientists from 153 countries have come together to warn that if we continue with business as usual, the result will be untold human suffering from climate change," said Dr Ripple.
The more people there are on the planet, the worse it is for the climate, the researchers argue in a new paper, published this week in the journal Sustainability Science.
"There are strong links between high rates of population growth and ecosystem impacts in developing countries connected to water and food security," said Dr Wolf.
"Given the challenges of food and water security, effective population policies can support achieving both social justice and climate adaptation, particularly when you consider the current and projected uneven geographical distribution of the impacts of climate change."
They acknowledge population control has earned a bad reputation, "partly due to forced sterilization campaigns and China's one-child policy". But they reckon if done right, it can not only fight climate change but promote "human rights, equity and social justice" - such as through education for young women, ending child marriage and increasing the availability of family planning services.
"Three examples of countries in which improved education for girls and young women may have contributed to significant fertility rate declines are Ethiopia, Indonesia and Kenya," Dr Ripple said.
"Among those nations, specific education reforms included instituting classes in local languages, increasing budgets for education and removing fees for attending school. Ethiopia also implemented a school lunch program, large-scale school construction took place in Indonesia, and primary school was lengthened by one year in Kenya."
But who's going to pay for it? The researchers say rich countries should, considering they're the ones responsible for most of the climate damage to date. Rich countries tend to have lower birth rates already, some below the rate of replacement, so they have to actually cut consumption, rather than just produce fewer offspring.
"It's not a balanced approach to focus on fertility rates without remembering that wealthy governments, corporations and individuals have been the primary contributors to carbon dioxide emissions and the main beneficiaries of fossil fuel consumption," said Dr Wolf.
"Overconsumption by the wealthy must be addressed immediately, for example through policies like eco-taxes such as carbon pricing," said Dr Ripple. "Reducing fertility rates alone is clearly not enough. The middle class and rich must be responsible for most of the needed reduction in emissions."
The long-term goal should not just be to reduce emissions but aim for "convergence" - equalising emissions output per capita between nations.
"Social justice and the climate emergency demand that equitable population policies be prioritized in parallel with strategies involving energy, food, nature, short-lived pollutants and the economy," said Dr Ripple. "With feedback loops, tipping points and potential climate catastrophe looming, we have to be taking steps in all of those areas and not ignoring any of them."
