Science·What on Earth?

From abandoning coal to saving forests, the big pledges from the UN climate summit

In this week's issue of our environment newsletter, we look at some of the big pledges made during the UN Climate Action Summit and the truth about biodegradable bags.

Also: The truth about biodegradable waste bags

(Sködt McNalty/CBC)

Hello, people! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

The big takeaways from a week of climate action

(Ludovic Marin/AFP/Getty Images)

The United Nations Climate Action Summit this past week featured a lot of drama and intrigue, from Greta Thunberg's pithy speech to U.S. President Donald Trump's 10-minute drop-in appearance to climate strikes, which are set to escalate again on Friday.

Some observers expressed disappointment at the lack of bold plans from individual countries in reducing carbon emissions. But there were pledges made on the margins, as cities, civil groups, companies, banks and pension funds announced their own initiatives to meet the targets laid out in the Paris Agreement to limit global warming this century to 1.5 C.

All talk? Maybe. Here are some of the announcements that could make a difference.

More ambitious country targets

Finland has committed to achieving carbon neutrality (that is, offsetting all its emissions) by 2033 and aims to be the first industrial economy to go carbon negative (sucking up more carbon than it emits). It's pushing other EU countries to follow suit. Sixty-six countries have promised to make their climate goals more ambitious and 30 swore to be carbon-neutral by mid-century.

Abandoning coal

Canada and Great Britain lead the Powering Past Coal Alliance, which includes countries, states or regions and corporations committed to ending the building of coal plants by 2020, and picking up the pace of transition to renewables. This week, Germany, the largest user of coal in Europe, and Slovakia joined the alliance. This list tracks all the companies that have committed to divesting from coal financing.

Companies buy in

A group of 87 major companies in 27 countries — including The Co-operative Group, IKEA, Danone, L'Oréal and Nestlé — say they will set climate targets for their entire value chain in line with the Paris targets. According to the UN, these companies have combined annual direct emissions equivalent to 73 coal-fired power plants.

Responsible investing

The Asset Owner Alliance, a self-styled group of pension funds and insurers with more than $2 trillion US in investments, committed to carbon-neutral investment portfolios by 2050 in hopes of spurring others to make similar moves. The group includes Zurich Insurance, German insurer Allianz and La Caisse de dépôt et placement du Québec.

Committing to nature

The Global Campaign for Nature aims to conserve 30 per cent of the Earth's lands and oceans by 2030. Central American countries are collaborating to restore 10 million hectares and Central African states set goals to preserve and restore their rainforest.

Saving the rainforest

International donors pledged $500 million US to protect the rainforest, including the Amazon, which suffered record fire damage this year. France, Chile and Colombia met on the sidelines of the UN gathering, pledging to stop deforestation and restore degraded forests. (Brazilian President Jair Bolsonaro, a climate change skeptic, did not participate.)

Help for developing countries

French President Emmanuel Macron has the backing of European countries for the Green Climate Fund, which helps poorer countries with climate issues. With the U.S. having pulled out, Macron urged other countries to step up to bring the fund to $10 billion. A group of 24 national and regional banks that work in developing countries is putting together financing to make poor countries more resilient, aiming to have $1 trillion to invest by 2025.

A call for 'climate disclosure'

Mark Carney, governor of the Bank of England, told the UN that climate issues must be at the heart of financial decision-making. He called for mandatory disclosure of climate impact and climate risk management by corporations. The U.K., Canada and the EU are already moving toward such disclosure, but Carney says it must be universal.

Susan Noakes

Reader feedback

Last Friday, an estimated four million people worldwide marched for climate action. This Friday, environmental demonstrators will do it again, with a large contingent expected in Canadian cities. Here's what What on Earth? readers are doing:

Debra Hayes said she booked off work on Friday to attend the climate strike event in Toronto. Elizabeth Robinson said she will be marching in Montreal as part of La planète s'invite en santé, a group made up of Quebec health workers.

Jane Caswell, who lives in Edmonton, said she took the last few weeks off work "to avidly participate in and watch the global events unfold." Caswell added that she has had a "Sept. 27th climate strike protest sign made for a couple of weeks." 

Karl Maier wrote in to say he, too, would be striking on Friday. He added the demonstrations are "a good way to send the message to our leaders, elected and otherwise, that 'business as usual' has ended. The climate is screaming in pain, let's answer with compassion and courage."

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Old issues of What on Earth? are right here.

The Big Picture: The cheapest forms of energy, by country

Transforming electrical grids worldwide is one of the biggest priorities in reducing greenhouse gas emissions. Many countries have been reluctant to relinquish high-carbon sources such as coal and natural gas because for a long time, they have been the cheapest resource for creating power. But that's changing. The cost of installing wind turbines and solar panels has come way down — plus, wind and sun are free and plentiful. As a result, the cheapest energy source for many countries has changed drastically in the last five years, as the graph below shows. (Note: The graph is on a loop, so if you can't take it all in at first glance, it will change back.)


Hot and bothered: Provocative ideas from around the web

  • We hear a lot about the ability of trees to sequester carbon. But did you know that whales have a similar power? Scientists have estimated that when it comes to carbon capture, one whale is equivalent to 1,000 trees. Among other things, whale poop leads to the proliferation of phytoplankton, which are excellent vessels for storing carbon.

  • Consumers have become increasingly aware of the garment industry's exorbitant use of water, as well as its carbon emissions. The simplest way to reduce fashion's environmental footprint is to buy fewer, better clothes. This service feature from the New York Times explains how to buy higher-quality pieces, from scrutinizing the blend of materials to doing "the tug test."

Trash talk: The truth about biodegradable bags

(Craig Chivers/CBC)

Back in July, the City of Ottawa made a shift to allow its residents to put plastic bags in the compost bin. People noticed. 

After the plastic bag bill passed, many people took to Twitter to voice their disapproval, calling it a "stupid policy" for "the lazy," and "idiotic at a time when in many jurisdictions, plastic bags are trying to be phased out."

While it may seem odd to allow plastic bags in the green bin, many people find it makes the process of capturing household organic waste a little more tidy. Municipalities that allow it skim plastic bags off early in the disposal process.

Many jurisdictions actually encourage the use of biodegradable bags, and consumers buy them with the belief that they will decompose with the rest of the organic waste. But that isn't always true. 

Even in the landfill, compostable plastics may not degrade, according to a study done by the University of Plymouth in the U.K. The study tested five types of commonly used plastic bags, including ones labelled "compostable" and "biodegradable," to see how well they break down in different conditions. They tested the bags in both soil and sea, where they remained intact, exactly like regular plastic.

Tom Szaky, CEO of TerraCycle, a U.S. business that has gained a reputation for recycling the "non-recyclable," has written about this. In his book Linear to Circular: The Future of Packaging, he writes that most consumers "don't realize … that biodegradable bioplastics will break down only under the right conditions — those of a specific industrial composting facility."

Szaky emphasized that "even if that happens, [the bags] won't contribute value to the compost, unlike coffee grounds or leaves, which have a wide range of micro- and macronutrients as well as a living ecosystem of bacteria and other microbes."

Even if they could create those perfect conditions, some municipalities have banned compostable plastics from green bins, including Toronto. 

The City of Toronto website says:  "There are many types of products that call themselves 'degradable.'

"They may be degradable in the presence of certain components … and are made to degrade in a certain time period. This time period and conditions may not match the actual conditions in a processing facility."

The Metro Vancouver solid waste site states that "plastics, including those marked biodegradable, do not belong in the compost as they do not break down properly during processing."

People who are confused or concerned about any kind of plastic have other options. Many municipalities suggest lining your bin with newspaper for an easier clean or simply not lining the bin at all. They also suggest washing out your bins regularly and putting them on the curb consistently, even when they're not full. 

Or you could simply call your municipality's facility and ask what they accept. 

Taylor Logan

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Editor: Andre Mayer | Logo design: Sködt McNalty


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