Healthy forests protect our climate and moderate our weather. As the ‘Godzilla’ El Niño builds in the weeks ahead of Paris talks, it is a timely warning that deforestation is partly to blame for its impacts
Indonesia is smouldering and Godzilla is to blame. But even though this is reality, not a monster movie, there is still a hero: the tropical rainforest.
This year’s El Niño, the ocean-traveling climate cycle notorious for throwing the weather off kilter, is nicknamed “Godzilla”. While it is projected to deliver plenty of rain to some parts of the world, including drought-parched California, it is already causing dangerously dry conditions in the tropics. Papua New Guinea, for example, is experiencing its worst drought in decades, which spells doom for coffee and food crops.
The last time El Niño was this intense, in 1997, five million hectares of rainforest went up in smoke in Indonesia at a time when rain usually falls in sheets. The forest fires generated gigatonnes of carbon dioxide, equivalent to 13-40% of the world’s fossil fuel emissions at the time. The resulting haze, which spanned an area from northern Australia to the Philippines to Sri Lanka, caused widespread health problems and grounded airplanes.
Standing, healthy forests, the Earth’s “sweat glands”, pump moisture into the atmosphere, providing the globe with its greatest defense against droughts, forest fires and other weather-related disasters. Without this buffer, we’re more exposed and vulnerable to the whims of extreme weather.
To maintain an effective buffer, it is imperative that global efforts to protect forests are accelerated. Tropical forests are important climate bulwarks, and the impact of cutting them down packs a wallop beyond the release of the vast stores of carbon they hold. Tearing down forests also changes the earth’s surface, triggering major shifts in rainfall and increases in temperature worldwide that can be just as disruptive to the climate and weather as those caused by carbon pollution.
One of the most ambitious forest commitments to date, last year’s New York Declaration on Forests, recognises the “double whammy” impact of deforestation on the climate and weather. This agreement among corporations, governments, NGOs and indigenous groups to end deforestation by 2030 includes a call to restore and regrow forests in addition to protecting already-standing forests.
Planting forests eventually stores carbon. But it takes an agonizingly slow 50-100 years or more for new forests to absorb the amount of carbon released when a tropical forest is cleared and burned. It is far more effective to prevent the forests from falling in the first place. But planted forests can provide a different, underappreciated benefit to the world’s climate and weather – and they do so more quickly than they recover carbon or the plant and animal life they once held.
Within a decade, most planted forests in tropical regions develop a closed canopy, as branches from one tree touch those of the next. At this stage of growth, they transform substantial amounts of water in the soil – which they reach via roots far deeper than found in crops or grasses – into moisture in the air, which cools the atmosphere above and the area around them. This process also generates moist conditions and rainfall locally and in the surrounding region.
It also generates the mass movement of air and conditions in the upper atmosphere that ultimately influence rainfall and temperature, both close by and far away. When forests are standing, they give us our climate and they can help protect us against a changing climate.
But when forests are cut down, these systems are disrupted. Changes in circulation due to tropical deforestation ultimately hit the upper atmosphere, where they cause ripples, or teleconnections, that flow outward in various directions, similar to the way in which an underwater earthquake can create a tsunami. The atmosphere connects climate in one place to climate in the rest of the world.
Deforestation across the tropics, therefore, might alter growing conditions in agricultural areas in south-east Asia, South America and Africa, and as far away as the US Midwest, Europe and China. This means that cutting down forests could imperil the world’s breadbaskets, even those thousands of miles away from the tropical forest belt – with dire implications for the ever-increasing demands on the world’s food supply.
As the Godzilla El Niño bears down and the climate talks in Paris heat up, remember that deforestation is partly to blame for its impacts. Deforestation worsens droughts, making El Niño more damaging than it would otherwise be. Healthy forests protect our climate and moderate our weather.
The international community assembling in Paris in December cannot keep global warming below 2C without both protecting the world’s remaining tropical forests and restoring vast areas of tropical forest that have already been lost. If we do not ensure the future of our forests, this year’s Godzilla El Niño may prove to be a puny harbinger of the monsters to come.
By Deborah Lawrence (an environmental sciences researcher at the University of Virginia), The Guardian of London