Sustainable Missoula: Can trees really save the planet? It’s complicated.
For those plugged in this summer, even with national politics overwhelming the airwaves, it would be hard to miss the news about forests and climate change. July’s headlines announced “The Trees will Save Us." And then just days ago comes the United Nations IPCC report about the global implications of climate, food and land use, with headlines like “Save the Forests (they’re not for beef).” If you’ve been out hiking in the forests or avoiding the news, you may have missed the plethora of critical and at times conflicting reports.
We thought this is a good time to help make sense of what we know and don’t know and, because we at Climate Smart Missoula like to advocate what we can actually do.
We’re lucky in Missoula to have top-notch researchers at the University of Montana and at our federal agencies. We’ve been digging into these recent studies with local climatologist Nick Silverman, and we find ourselves wondering: How can the top science journals across the world publish seemingly divergent articles about the role of trees in addressing the global climate crisis? Can trees be both part of the solution and part of the problem? It seems they can.
First, according to the July study that created all the positive headlines about the benefits of trees, here’s the explanation. Because trees soak up CO2, they’ve long been considered a valuable tool to fight global warming. However, accurate estimates of how many trees the world can support have been hard to produce and evaluate. This new Science report aims to show not just how many trees can be grown, but where they could be planted and the impact they would have on carbon emissions worldwide. The result is an awesome map of our world with trees.
According to a smart piece in VOX, “The worldwide assessment of current and potential forestation using satellite imagery appeared [July 4] in the journal Science. It estimates that letting saplings regrow on land where forests have been cleared would increase global forested area by one-third and remove 205 billion metric tons of carbon from the atmosphere. That’s two-thirds of the roughly 300 billion metric tons of carbon humans have put up there since the dawn of the Industrial Revolution.”
Cool. A silver bullet. Let’s plant trees everywhere and go on with our carbon-consumptive lives now that we know the trees will save us. Right? Not so fast.
Reforesting large swaths of lands degraded forest lands is warranted, especially in the tropics (think Brazil), but of course it’s more complicated. Some of those places may already be providing other ecosystem and human functions, and it’s not always easy to reforest successfully, given the changing climate.
Earlier this year, in a January 2019 article in Nature, we were cautioned about the forest/climate complexities: “Many scientists applaud the push for expanding forests, but some urge caution.... Although trees cool the globe by taking up carbon through photosynthesis, they also emit a complex potpourri of chemicals, some of which warm the planet. The dark leaves of trees can also raise temperatures by absorbing sunlight. Several analyses in the past few years suggest that these warming effects from forests could partially or fully offset their cooling ability.”
The Nature piece continues: “Researchers have known for decades that tree leaves absorb more sunlight than do other types of land cover, such as fields or bare ground. Forests can reduce Earth’s surface albedo, meaning that the planet reflects less incoming sunlight back into space, leading to warming. This effect is especially pronounced at higher latitudes and in mountainous or dry regions, where slower-growing coniferous trees with dark leaves cover light-coloured ground or snow that would otherwise reflect sunlight. Most scientists agree, however, that tropical forests are clear climate coolers: trees there grow relatively fast and transpire massive amounts of water that forms clouds, two effects that help to cool the climate.”
Ah the complexity! It reminds us first and foremost how we need more science and more answers. And then this week, here’s the headline:
There’s a lot packed into this newest report. From the need to protect wetlands, to a mandate to waste less food and change our diets. In relation to forests, there’s a clear call to work worldwide to stop converting tropical rainforests into cattle pastures. There’s some hope in our ability to work together, as consumers, financiers, and political leaders. Protecting forested lands matter.
We’re also struck by news around the world of what people are doing to build a more resilient world. For example, you may have seen this headline: Ethiopia 'breaks' tree-planting record to tackle climate change. In one day the country planted over 350 million trees, and they aim to plant 4 billion! Hopefully this is reforestation of previously forested areas (good!) and will these seedlings get the water and care they need to survive. That final point is something we’ve learned from our tree advocates right here in Missoula. We need to care for the trees we plant.
And this brings us back here. We love trees in towns and around homes. They keep us mentally and physically healthy and contribute positively to everything from biodiversity to reducing the “urban heat island” effect during hot summer days.
Our friends at Trees for Missoula and Missoula’s Parks & Recreation Urban Forestry team plant and care for trees across our community. As we mentioned in last week’s column, we can’t plant a tree and ignore it- we need to water our trees this time of year. Even if the rains visit us this weekend, hot, dry days are destined to return.
So from Brazil to Ethiopia to Missoula, there are a wide range of things to learn, considerations and things that forest and climate advocates can do. Like:
Support Science and Leadership!
- We’re lucky to have such top-notch researchers at the University of Montana. Support them. Get your tree-loving niece to consider attending college here. Hit up some of their upcoming science talks.
- Ask informed questions of our elected leaders and call them out when they make dubious climate or forest claims, ones that ignore the nuances.
- Don’t just vote — work to elect leaders that believe in advancing science and appreciate the challenges of living in fire-adapted, climate challenged, forested landscapes. Like all meaningful climate solutions enacted at scale, we need political will.
Support and Grow Trees!
- Plant a tree around your home or business and care for it. Plant the right tree in the right place!
- Use trees to shade buildings and youre A/C unit (save energy!); we’ve more on our website.
- Plant a tree in your neighbor’s yard or if you don’t have a yard, get a big pot (indoor plants help clean the air) or water nearby boulevard trees.
- Save the rainforest – donate, hold the beef and palm oil, write letters.
- Consider wood products if you’re embarking on a building project.
Stay Open and Stay Tuned!
- Embrace the complexity – it’s what keeps it interesting.
- Don’t believe everything you read on the internet. There are no silver bullets. We still need to reduce our carbon pollution, and fast.
- Look for an upcoming Sustainable Missoula piece that dives deeper into more ways our forests could be connected to clean electricity, wildfire adapted forests, and the timber used effectively in our buildings.
The final upshot of all this: more science is warranted, trees and forests are (mostly) good, and when it comes to our climate emergency, trees alone cannot save us. There’s no getting around our world-wide need to stop burning fossil fuels. Yet it’s beyond wonderful that trees can both mitigate climate by soaking up CO2 and help us adapt to the changes here and coming, building equity resiliency into our community. Thanks for helping out in whatever ways you can.
Amy Cilimburg is the Executive Director for Climate Smart Missoula.
This column is part of a weekly series, Sustainable Missoula, which highlights community sustainability effort and is brought to you – via the Missoula Current – every Friday by Climate Smart Missoula and Home ReSource.
Upcoming Sustainability Events:
August 20 & 21. Wildfire Smoke Ready Businesses and Residences. Mini-workshops with Climate Smart, the Missoula Health Department and co-sponsored by the Missoula Federal Credit Union. Details here.
August 23-24. Help “green” the annual downtown River City Roots Festival. Volunteers needed for two-hour shifts both days – head HERE to sign up.
September 7. Free Cycles Climate Ride. Community cycling event to raise awareness about climate change and benefit Free Cycles’ programs. Different ride lengths available starting at 9am.
September 14. Spontaneous Construction – Home ReSource’s fabulous annual creative reuse art event. You can still register your team. Or just plan to come by for the festivities. Details here.
September 20. Global Climate Strike! People of all ages all across the globe are striking on Friday, 9-20, and planning is underway for a rally and festivities here in Missoula. Find out about local actions here.
September 28, Missoula's second annual Clean Energy Expo. 10 am-3 pm, Caras Park. Join Climate Smart Missoula, The Montana Renewable Energy Association and many others to learn about and celebrate climate solutions and clean energy. Learn more here and contact Abby at Climate Smart if you'd like to co-sponsor or volunteer.
All summer. Join the Logjam Presents Green Team. The Green Team will assist with teaching patrons how to use Zero Waste stations at events. Sign up here.
View more climate and energy events via Climate Smart Missoula’s Calendar.
There are many more conservation events for 2019 HERE.