Last week, the government of Ethiopia announced its citizenry had planted more than 350 million trees in one day, part of a plan to reforest the country by planting 4 billion native saplings before the rainy season ends in October.
Forests covered more than a third of Ethiopia in 1900; now it’s less than 4 percent, according to the United Nations.
Over the whole planet, forests are disappearing. The World Bank estimates that half a million square miles of forest were lost between 1990 and 2016, cut down or burned to make way for agriculture — soy and palm oil plantations, for instance — and for livestock grazing, logging and development.
Loss of wide swaths of forest impact wildlife, water quality, erosion and even air temperature and quality.
In seventh grade, my school gave every student a fir sapling on Arbor Day. After lunch, we went out to the playing fields behind school and planted our little trees, in lines parallel to the woods that grew on three sides of the field.
We were adding trees to an already green space. A nice gesture, but it might have been more helpful if we had built green islands in the parking lot, those acres of blacktop that bake in the sun, heating up the air around them.
If you parked your car in a big lot somewhere during the recent heat wave, you know what I’m talking about. You could feel the heat rising off the blacktop, and it’s tough getting into a sweltering car at the end of the day when it’s been sitting in a hot lot for hours. The bigger the expanse of blacktop, the hotter the lot.
Green islands and shade trees in a parking lot can do plenty to change that. The National Wildlife Federation says trees in parking lots can lower surface temperatures by as much as 36 degrees Fahrenheit through shade and transpiration — the evaporation that green plants do through their leaves.
The EPA says the same “Trees and vegetation lower surface and air temperatures by providing shade and through evapotranspiration. Shaded surfaces, for example, may be 20–45 degrees Fahrenheit cooler than the peak temperatures of unshaded materials.”
Imagine what planting trees could to do to slow rising global temperatures. Trees absorb and store carbon, prevent erosion and cool the air. Planted strategically around buildings, they can lower energy usage, reducing both cost and emissions. Planted in large swaths, they can mitigate warming trends.
That’s what Ethiopia is hoping for. The country lost 10,000 square miles of forest between 1990 and 2015, the U.N. Food and Agriculture Agency said, as land was cleared for fuel, lumber and agriculture. Without trees drawing water from deep in the soil and evaporating it into the air, the climate becomes drier, increasing the likelihood of drought.
Ethiopia has plenty of company its efforts to re-tree the country. The African Forest Landscape Restoration Initiative is a continent-wide plan to reforest nearly 400,000 square miles of land in the next decade.
The Earth Day Network’s Canopy Project promotes tree planting worldwide, but particularly in poorer countries and where deforestation has caused the loss of environmentally critical areas like rain forests. The project has a goal of planting 7.8 billion trees in 2020, the 50th anniversary of the first Earth Day.
That’s roughly one tree for every person on Earth. We can all help.
Greenpoint appears every other Sunday. Look for it next on Aug. 11. Reach Margaret Hartley at [email protected] or @Hartley_Maggie on Twitter. Opinions expressed in Greenpoint are hers and not necessarily the newspaper’s.