Millions of poor people in Southern Africa, Asia and Central America face hunger and poverty this year and next because of droughts and erratic rains as global temperatures reach new records, and because of the onset of a powerful El Niño – the climate phenomenon that develops in the tropical Pacific and brings extreme weather to several regions of the world.

Despite record global temperatures in 2014, an El Niño did not appear; nevertheless, in an unusual development, the climate in many parts of the world behaved as if one was occurring and growing seasons were seriously disrupted, mainly by drought. Temperatures have continued to soar this year and now an El Niño has indeed developed. It could be the most powerful since 1997-98, 2 which caused climate chaos and humanitarian disasters in many countries. With the boost of El Niño, unprecedentedly high temperatures are likely to continue into 2016.

Already, Ethiopia is facing a major emergency: 4.5 million people are in need of food aid because of successive poor rains this year. Floods, followed by drought, have cut Malawi’s maize production by more than a quarter; between two and three million people may face a food security crisis by February next year, at the peak of the lean season. In Zimbabwe, drought has reduced the maize harvest by 35 percent, and it is estimated that 1.5 million people will need assistance in early 2016. Farmers across the ‘dry corridor’ of Central America have been hit by drought for two years running, with huge harvest losses. Disruption to maize production in both Southern Africa and Central America is driving a surge in the price of maize on local markets, making it increasingly hard for people living in poverty to afford sufficient food.

Over the next few months the El Niño will attain maximum strength. This will coincide with the coming rains in Southern Africa, due from November onwards. Meteorologists predict a high probability of below-average rains again as a result. A second successive poor rainy season across Southern Africa will bring serious food security problems next year. The next rains in northern Ethiopia from March may also be affected.

El Niño has also already reduced the Asian monsoon over India, and is raising the odds of a prolonged drought in East Asia, coinciding with the planting and early development of the main rice crop in Indonesia; if world prices for rice increase there could be knock-on effects on poor urban consumers in import-dependent West African countries. In Papua New Guinea, 1.8 million people have been affected by drought already and El Niño will make this worse.

Yet meteorologists and international agencies such as the World Food Programme have provided ample warning of El Niño; the regions likely to be affected and the potential effects are understood. Agencies such as Oxfam have been monitoring conditions on the ground, helping communities cope with the current food crises and, increasingly, sounding the alarm that more must be done. Disasters are not inevitable at this point. If governments and agencies take immediate action, as some are doing, then major humanitarian emergencies next year can be averted. Prevention is better than cure.

In the immediate future, increasing climatic disruption, driven by rising temperatures, threatens to increase pressures on the humanitarian system at a time when resources and capacity are under enormous strain. Furthermore, scientists are warning that recent events could signify that big changes may be underway in the Earth’s climate system, 4 driven by rising surface temperatures and changes in major atmospheric and oceanic circulation systems such as those which give rise to El Niño.

Warming seas could double the frequency of the most powerful El Niños, and as global warming creates more and more sea-surface temperature ‘hot spots’ in the world’s oceans, and wind systems change as a result, extreme weather and greater climate disruption may be what a ‘normal’ future looks like if greenhouse gas emissions are not urgently and drastically reduced.

The combination of record warmth one year followed by an El Niño the next is unique and the climatic implications are uncertain. If 2016 follows a similar pattern we are entering uncharted waters.

Just one week after leaders adopted an historic new goal of eradicating hunger by 2030, as part of the package of Sustainable Development Goals, this unfolding crisis shows the scale of threat that climate change poses to its realization. For those leaders, the first test of their commitment will be to strike an agreement at the UN climate talks in Paris this December that delivers for the women, men and children on the frontlines of climate change.