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The world’s boreal forests may be shrinking from climate change

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07 Nov, 2023

This post was originally published on Sustainability Times

Source: Sustainability Times

photo: Pixabay/Bergadder

Earth’s boreal forests circle our planet’s far northern reaches, just south of the Arctic’s treeless tundra. If the planet wears an Arctic ice cap, then the boreal forests are a loose-knit headband wrapped around its ears, covering large portions of Alaska, Canada, Scandinavia and Siberia.

The boreal region’s soils have long buffered the planet against warming by storing huge quantities of carbon and keeping it out of the atmosphere. Its remoteness has historically protected its forests and wetlands from extensive human impact.

These two traits rank boreal forests among the most important ecosystems on Earth. In addition, numerous species of mammals, fish, plants, insects and birds make these forests home.

For over two centuries, scientists have recognized that climate plays a key role in determining the geographic zones of plant communities. Because boreal forests and soils face subzero winters and short summers, these forests and the animals that live in them are shifting northward as temperatures rise.

However, boreal forests’ northward advance has been spotty and slower than expected. Meanwhile, their southern retreat has been faster than scientists predicted. As scholars who study northern ecosystemsforests and wetlands, we see concerning evidence that as the world warms, its largest forest wilderness appears to be shrinking.

The largest wilderness on Earth

Boreal forests contain billions of trees. Most are needleleaf, cone-bearing conifers, but there also are patches of broadleaf species, including birch, aspen and poplar. They support millions of migratory birds and iconic mammals like brown bears, moose and lynx.

Photo: Pixabay/FelixMittermeier

These trees and the soils around their roots help regulate Earth’s climate, in part by pulling carbon dioxide out of the atmosphere, where it would otherwise act as a greenhouse gas. The trees use this carbon to grow roots, trunks and leaves, which eventually turn into carbon-rich soil once the tree dies. Significant changes to the forests will translate to changes in global climate.

These forests are warming at rates well above the global average. Rising temperatures directly affect the growth and survival of trees and, in turn, their ability to store carbon.

Tracking forests from space

Satellites are invaluable for tracking how boreal forests have changed in recent decades and whether these changes are consistent with an overall northward shift. Researchers can use satellites to monitor year-to-year changes in forest characteristics, such as annual tree growth and tree cover.

Our recent studies using satellite data showed that tree growth and tree cover increased from 2000 to 2019 throughout much of the boreal forest. These changes occurred mainly in the coldest northern areas. However, there was limited evidence to indicate that forests were expanding past current tree lines.

Our studies also revealed that tree growth and tree cover often decreased from 2000 to 2019 in warmer southern areas of the boreal forests. In these regions, hotter and drier conditions frequently reduced tree growth or killed individual trees, while wildfires and logging contributed to tree cover loss.

Satellite data makes it clear that climate change is affecting both the northern and southern margins of the boreal forest. However, if tree cover loss in the south occurs more rapidly than gains in the north, then the boreal forest will likely contract, rather than simply shifting northward.

Zooming in to understand forest change

Forests advance when individual tree seeds germinate and grow, but boreal trees grow slowly and require decades to reach a size that’s visible from space. Finding young trees whose presence would signal tree-line movement requires data from the ground.

In the late 1970s, one of us (David Cooper) documented that young spruce trees were growing at altitudes hundreds of yards higher and locations miles north of the highest-elevation cone-bearing trees in Alaska’s Brooks Range. Returning in 2021, we found those little trees had grown to be several yards tall and were producing cones. More importantly, 10 times the number of young spruces now grow above and beyond the tree line than during our first field forays.

Crisscrossing the boundary between Alaska’s boreal forest and its Arctic tundra on foot, we have found thousands of young boreal trees growing up to 25 miles north of established tree lines. Most grow where deeper snows fall, due to an Arctic Ocean version of the “lake effect”: Cold air moves across open water, picking up warmth and moisture, which then falls as snow downwind.

Photo: Pixabay/Valiphotos

Retreating sea ice leaves more open water. This generates stronger winds that propel tree seeds farther and more snowfall that insulates seedlings from harsh winter conditions. The result is that trees in Alaska’s Brooks Range are rapidly moving into the treeless tundra. However, these rapid expansions are localized and do not yet happen everywhere along the northern tree line.

The future face of boreal forests

Our combined research shows that boreal forests are, in fact, responding to rising temperatures. But rapid rates of climatic change mean that trees likely can’t move northward at a pace that keeps up with their loss in the south.

Will trees in the far north ever catch up with climate and prevent forest contraction? At this point, scientists simply don’t know. Perhaps the newly established trees in the Brooks Range herald such an expansion. It’s also unclear whether the northern parts of boreal forests can accumulate enough carbon through increased growth to compensate for carbon losses in the south.

If boreal forests are indeed on the verge of contracting, they will eventually disappear from their current southern edge. This would harm many native and migratory animals, especially birds, by reducing their boreal habitat. The forests also are culturally important to several million people who call them home, such as Canada’s aboriginal communities.

Monitoring boreal forests around the world more closely, using both satellite data and on-the-ground measurements, will help fill out this picture. Only then can researchers hope to glimpse the future of one of the Earth’s last wildernesses.

This article was written by Ronny Rotbarth, a PhD candidate of Arctic and Sub-Arctic Ecology at Wageningen University; David J. Cooper, a senior research scientist emeritus at Colorado State University; Logan Berner, an assistant research professor of Global Change Ecology at Northern Arizona University; and Roman Dial, a professor of Biology and Mathematics at Alaska Pacific University. It is republished from The Conversation under a Creative Commons license. Read the original article.

The post The world’s boreal forests may be shrinking from climate change appeared first on Sustainability Times.

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Taking the electronic pulse of the circular economy

Taking the electronic pulse of the circular economy

In June, I had the privilege of attending the 2025 E-Waste World, Battery Recycling, Metal Recycling, and ITAD & Circular Electronics Conference & Expo events in Frankfurt, Germany.

Speaking in the ITAD & Circular Electronics track on a panel with global Circular Economy leaders from Foxway Group, ERI and HP, we explored the evolving role of IT asset disposition (ITAD) and opportunities in the circular electronics economy.

The event’s focus on advancing circular economy goals and reducing environmental impact delivered a series of insights and learnings. From this assembly of international expertise across 75+ countries, here are some points from the presentations that stood out for me:

1. Environmental impact of the digital economy

Digitalisation has a heavy material footprint in the production phase, and lifecycle thinking needs to guide every product decision. Consider that 81% of the energy a laptop uses in its lifetime is consumed during manufacture (1 tonne in manufacture is equal to 10,000 tonnes of CO2) and laptops are typically refreshed or replaced by companies every 3–4 years.

From 2018 to 2023, the average number of devices and connections per capita in the world increased by 50% (2.4 to 3.6). In North America (8.2 to 13.4) and Western Europe (5.6 to 9.4), this almost doubled. In 1960, only 10 periodic table elements were used to make phones. In 1990, 27 elements were used and now over 60 elements are used to build the smartphones that we have become so reliant on.

A key challenge is that low-carbon and digital technologies largely compete for the same minerals. Material resource extraction could increase 60% between 2020 and 2060, while demand for lithium, cobalt and graphite is expected to rise by 500% until 2050.

High growth in ICT demand and Internet requires more attention to the environmental footprint of the digital economy. Energy consumption of data centres is expected to more than double by 2026. The electronics industry accounts for over 4% of global GHG — and digitalisation-related waste is growing, with skewed impacts on developing countries.

E-waste is rising five times faster than recycling — 1 tonne of e-waste has a carbon footprint of 2 tonnes. Today’s solution? ‘Bury it or burn it.’ In terms of spent emissions, waste and the costs associated with end-of-life liabilities, PCBAs (printed circuit board assembly) cost us enormously — they generally achieve 3–5% recyclability (75% of CO2 in PCBAs is from components).

2. Regulating circularity in electronics

There is good momentum across jurisdictions in right-to-repair, design and labelling regulations; recycling targets; and voluntary frameworks on circularity and eco-design.

The EU is at the forefront. EU legislation is lifting the ICT aftermarket, providing new opportunities for IT asset disposition (ITAD) businesses. To get a sense, the global market for electronics recycling is estimated to grow from $37 billion to $108 billion (2022–2030). The value of refurbished electronics is estimated to increase from $85.9 billion to $262.2 billion (2022–2032). Strikingly, 40% of companies do not have a formal ITAD strategy in place.

Significantly, the EU is rethinking its Waste Electrical and Electronic Equipment (WEEE) management targets, aligned with upcoming circularity and WEEE legislation, as part of efforts to foster the circular economy. A more robust and realistic circularity-driven approach to setting collection targets would better reflect various factors including long lifespans of electronic products and market fluctuations.

Australia and New Zealand lag the EU’s comprehensive e-waste mandated frameworks. The lack of a systematic approach results in environmental degradation and missed positioning opportunities for businesses in the circular economy. While Australia’s Senate inquiry into waste reduction and recycling recommended legislating a full circular economy framework — including for imported and local product design, financial incentives and regulatory enforcement, New Zealand remains the only OECD country without a national scheme to manage e-waste.

3. Extending product lifecycles

Along with data security and digital tools, reuse was a key theme in the ITAD & Circular Electronics track of the conference. The sustainable tech company that I lead, Greenbox, recognises that reuse is the simplest circular strategy. Devices that are still functional undergo refurbishment and are reintroduced into the market, reducing new production need and conserving valuable resources.

Conference presenters highlighted how repair over replacement is being legislated as a right in jurisdictions around the world. Resources are saved, costs are lowered, product life is extended, and people and organisations are empowered to support a greener future. It was pointed out that just 43% of countries have recycling policies, 17% of global waste is formally recycled, and less than 1% of global e-waste is formally repaired and reused.

Right to repair is a rising wave in the circular economy, and legislation is one way that civil society is pushing back on programmed obsolescence. Its global momentum continues at different speeds for different product categories — from the recent EU mandates to multiple US state bills (and some laws) through to repair and reuse steps in India, Canada, Australia and New Zealand.

The European Commission’s Joint Research Commission has done a scoping study to identify product groups under the Ecodesign framework that would be most relevant for implementing an EU-wide product reparability scoring system.

Attending this event with the entire electronic waste recycling supply chain — from peers and partners to suppliers and customers — underscored the importance of sharing best practices to address the environmental challenges that increased hardware proliferation and complex related issues are having on the world.

Ross Thompson is Group CEO of sustainability, data management and technology asset lifecycle management market leader Greenbox. With facilities in Brisbane, Sydney, Melbourne, Canberra, Auckland, Wellington and Christchurch, Greenbox Group provides customers all over the world a carbon-neutral supply chain for IT equipment to reduce their carbon footprint by actively managing their environmental, social and governance obligations.

Image credit: iStock.com/Mustafa Ovec

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