EarthTalk®

Dear EarthTalk: I would like to plant a few new trees in my backyard, and am looking for guidance on which species are native and would benefit the local ecosystem. Where can I find this kind of information? -- Susan T., Bangor, ME

Home gardening is a great way to spend time outside, improve local ecosystems and learn more about botany and plants. When it comes to household gardening, natives are the key to success. Planting native species has numerous benefits, including providing food and habitat for native species, especially pollinators. Another important benefit is that native trees will thrive and spread naturally if they are planted in their native environment and suitable climate.

In order to plant the most well-suited flora for your garden to support a holistic, healthy ecosystem, here are some general principles to follow. As previously mentioned, go native! Secondly, look for pollinator friendly species. On a similar note, it could help to do some research on what species, both flora and fauna, are endangered or threatened in your area. Planting threatened tree species can help to support and grow their population numbers. Similarly, finding out which animal species are threatened and planting trees that could be beneficial to their survival would also be beneficial to supporting the local ecosystem. Finally, planting a variety of trees is a great way to support local biodiversity. High biodiversity levels support healthy, productive ecosystems.

Finding just the right species that ticks off all the boxes can be a daunting task. Luckily, there is a plethora of tools out there that can help. For example, Tree Wizard is a tool that helps find tree species that are suitable for specific climates and soil types. Another useful tool is the United States Department of Agriculture (USDA) Climate Change Tree Atlas. This tool specifically looks at how different species’ suitable ranges will change as a result of rising temperatures. This is a helpful tool for determining what tree species will thrive in the future in your area. You can also do research on which species are native to your specific state or region. Most states have an inventory of native trees available through their Department of Natural Resources, as well as an inventory of native animal species.

The bottom line is that planting trees, especially native ones, is massively beneficial to the ecosystem, and is an important step in fighting climate change. Trees provide major ecosystem services, especially carbon sequestration (removing carbon from the air). Trees store large amounts of carbon, and planting large numbers of them can create carbon sinks (defined as anything that absorbs more carbon from the atmosphere than it releases), decreasing the amount of greenhouse gases in the atmosphere. Other ecosystem services provided by trees include increases in biodiversity, support for local populations, and protecting soils from erosion and chemical runoff, which can help to keep water sources clean. Trees are the key to our future, so it is crucial that we do it right!

CONTACTS: Arbor Day Tree Wizard, arborday.org/shopping/trees/treewizard/intro.cfm; USDA Climate Change Tree Atlas, fs.usda.gov/nrs/atlas/. 

Dear EarthTalk: Is global warming creating the increase in turbulence on airplane flights?

-- Ginny C., Prescott, AZ

Air turbulence is defined as a sudden change in the speed, direction or air pressure in the atmosphere. Turbulence can cause abrupt changes in the motion of an airplane, ranging from small bumps to violent jolts that cause significant damage to aircrafts and injury to passengers. Air turbulence has increased rapidly in the last few decades. It is now the main cause of in-flight injuries and is estimated to cost the airline industry over $500 million annually.

The main causes of air turbulence are storms, jet streams—the bands of strong winds in the upper atmosphere—and mountains. In such cases, pilots can anticipate turbulence from pre-flight weather reports, sophisticated radar equipment and warnings from other pilots. But there is another kind of turbulence pilots have to contend with known as “clear-air turbulence,” which has no visible cause and cannot be detected by radars. This makes clear-air turbulence very perilous since pilots cannot warn passengers to buckle up and avoid injury. Clear-air turbulence is becoming more frequent; scientists and meteorologists predict that it will double in frequency between 2050 and 2080.

At the source of the rise in clear-air turbulence is global warming. As carbon emissions increase, greenhouse gases trap more heat in the troposphere (the layer closest to the Earth’s surface) instead of letting it rise into the stratosphere. This is causing a rising temperature difference between the two atmospheric layers, which in turn is causing large disruptions in the circulation patterns of atmospheric winds. These abrupt changes in the speed and direction of winds—known as “wind shear”—play a big role in creating the atmospheric disturbances that cause clear-air turbulence.

Although clear-air turbulence can occur at all levels of the troposphere in which airplanes cruise, they are most likely at the altitudes where the jet streams flow. Meteorologists have found that jet streams are experiencing 15 percent more wind shear than they did 40 years ago.

Can anything be done to avoid clear-air turbulence? Pilots could avoid flying in the four jet streams that circle the earth, and could limit flying through regions known to have high clear-air turbulence. The industry could invest in aircraft designs that improve aircraft stability and develop technology to detect clear-air turbulence. But pilots fly in the jet stream to shorten flight times and use less fuel. Thus, taking these steps will lead to longer flights, higher costs, more fuel consumption and carbon emissions, further increases in global warming and more turbulence, not less.

A better solution is to tackle rising clear-air turbulence at its source: by reducing global warming. Among other things, governments should accelerate policies that mitigate climate change such as carbon taxation, and provide incentives for clean energy adoption. Businesses should speed up investment in clean-energy products, services and infrastructure. And ordinary people should reduce their consumption of fossil-fuels by conserving energy, using public transit, recycling and participating in citizen science projects that mitigate climate change.

CONTACTS: Professor Paul Williams, International expert on air turbulence and climate change, www.port.ac.uk/school-of-biological-sciences/staff/john-mcgeehan.html; Petition to Stop Global Warming, https://preserve.nature.org/page/81465/petition/1?locale=en-US. 

Dear EarthTalk: How is America's outdated power grid inhibiting efforts to fight climate change?

-- Jim S., Milwaukee, WI

Our outdated power grid is indeed a significant hindrance to efforts to combat climate change. One of the key issues is the grid’s limited capacity to integrate renewable energy sources (solar, wind, etc.), a needed step if we’re to make the transition to a clean energy economy. Today’s grid is made up of a patchwork of local and regional interests often at odds with one another and developed to process locally sourced coal and gas into electricity that rarely gets transported more than a few dozen miles away.

To take full advantage of renewables, these local and regional utilities need to coordinate on the production and placement of thousands of miles of new high voltage transmission lines that could send electricity generated by wind and solar for thousands of miles across multiple grid regions. But without clear financial incentives, utilities aren’t in any rush to pursue such endeavors.

A key challenge of renewable energy generation is its intermittency. Solar and wind power is variable depending on weather conditions, making it essential to have a grid capable of balancing supply and demand in real-time. An outdated grid with limited energy storage capacity and transmission capability can’t effectively manage the fluctuations in renewable energy production. So renewable energy gets wasted while the grid keeps using fossil fuels to meet demand during times of low renewable generation.

Moreover, an outdated power grid falls short in integrating electric vehicles (EVs) into the transportation sector, a crucial component of efforts to reduce greenhouse gas emissions. EV adoption is on the rise, but the existing grid is ill-equipped to support a widespread charging infrastructure. This hinders the growth of the EV market. To fully realize the potential of EVs as a climate solution, a grid must be able to support increased demand from charging stations and manage the associated load fluctuations.

Outdated power grid vulnerabilities are further exacerbated by the increasing frequency and intensity of extreme weather events linked to climate change. Aging infrastructure is more susceptible to damage from storms, hurricanes and wildfires, resulting in prolonged power outages and disruptions. These events not only have immediate impacts on public safety and health but also impede climate change mitigation efforts by hampering renewable energy generation and slowing down the restoration of power supply.

To address these challenges, significant investments in grid modernization are essential. Upgrading the power grid to a smart grid, equipped with advanced sensors, automation and two-way communication can enhance grid resilience and flexibility. Smart grid technologies enable real-time monitoring and response, optimizing electricity distribution, and facilitating the integration of renewable energy sources. Additionally, expanding energy storage infrastructure, such as battery systems, can help mitigate the intermittency of renewable energy generation and provide backup power during outages.

CONTACTS: Americans for a Clean Energy Grid’s “Our Outdated Grid,” cleanenergygrid.org/our-outdated-grid/; Why the U.S. Electric Grid Isn’t Ready for the Energy Transition, nytimes.com/interactive/2023/06/12/climate/us-electric-grid-energy-transition.html.