Borley wood – restoration This view shows a area from which planted exotic conifer species have just been removed to allow site native species to re-assert themselves (NVC W8 ash/maple woodland type), October 17, 2006.
A recent study “A Century of Reforestation Reduced Anthropogenic Warming in the Eastern United States” unveils a silver lining through the lens of historical reforestation efforts in the Eastern United States. Spanning over a century, these endeavors have contributed to the greening of landscapes and played a pivotal role in reducing anthropogenic warming across the region. This study revealed the significant impact of reforestation on local climate mitigation and underscores the potential of nature-based solutions in our fight against global warming.
The Cooling Effect of Reforestation
The research, conducted by a team of environmental scientists, reveals that reforestation in the Eastern U.S. has led to a noticeable cooling of both land surface and near-surface air temperatures. By analyzing ground and satellite-based observations, the study highlights a significant reduction in temperatures, with forests cooling the land surface by 1–2°C annually compared to adjacent grasslands and croplands. This cooling effect is most pronounced during the growing season’s midday, offering a natural buffer against the rising temperatures associated with climate change.
A Shift in Climate Trends
Interestingly, the study correlates the extensive reforestation efforts with the anomalous lack of warming in the Eastern U.S. throughout the 20th century. Unlike other North American regions that experienced substantial warming, the Eastern U.S. showed minor cooling trends, attributed to the biophysical impacts of reforestation. This phenomenon, often referred to as the “warming hole,” underscores the potential of strategic reforestation efforts in tempering regional climate trends.
Implications for Climate Adaptation
The findings of this study underscore reforestation’s dual benefits: sequestering carbon dioxide from the atmosphere and directly cooling the Earth’s surface. In the face of escalating climate change, reforestation emerges as a vital nature-based solution, offering a sustainable pathway for climate adaptation and mitigation. The study’s insights highlight the importance of preserving and expanding forested areas as a proactive measure against global warming.
Renewed Focus on Reforestation & Conservation
As we move forward, the study calls for a renewed focus on reforestation and forest conservation as key strategies in the global climate action agenda. By learning from the century-long reforestation efforts in the Eastern U.S., we can harness the power of nature to forge a cooler, more sustainable future for our planet.
The study provides compelling evidence of reforestation’s positive impact on climate. It serves as a call to action for policymakers, environmentalists, and communities worldwide to invest in reforestation as a practical and impactful climate solution.
The Alliance of CEO Climate Leaders shares an open letter for world leaders at COP27.
Alliance members know that limiting global warming to 1.5 degrees Celsius requires significant collaboration and shared responsibility between the private and public sectors.
Knowing this, the CEOs are ready to work side by side with governments to accelerate the transition to net zero.
More than 100 CEOs of large multinational organizations, all members of the Alliance of CEO Climate Leaders, have strong convictions that our ambitious climate targets can be realized only with the support of governments.
We recognize the positive progress to date. Emissions under current policies are projected to reach 58 GtCO2e in 2030, 2 GtCO2e lower than what it was in 2019, but still 25 GtCO2e higher than what is essential to limit warming to 1.5 degrees Celsius. This gap is equivalent to the annual emissions of 5.4 billion cars. Unfortunately, assuming full implementation of unconditional NDCs still results in a 23 GtCO2e gap (2019 and 2022 UNEP Emissions Gap Report). Governments must raise their ambitions and enact policy changes to close this gap, otherwise we face a significant threat to the existence of human life and nature.
This letter outlines the actions we believe governments and businesses need to take to unlock the potential of the private sector and to move towards a path that limits global warming to 1.5 degrees Celsius.
We’re in this together to solve the climate crisis
We, the Alliance of CEO Climate Leaders, are ready to work side-by-side with governments to deliver bold climate action. We encourage all business leaders to set science-based targets to halve global emissions by 2030 and reach net zero by 2050 at the latest.
The global impact on food and energy prices, notably due to the war in Ukraine, continues to hurt households, businesses and economies worldwide. The crisis is a stark reminder of the fragile nature of the current energy and food systems, which are still dominated by fossil fuels. Leaders at the United Nations Climate Change Conference (COP27) have the chance to make this a historic turning point towards cleaner, more affordable and secure energy and food systems. We, therefore, welcome Egypt’s hosting of COP27 this year and Africa’s leadership on climate action, adaptation, resilience and a just transition.
Accelerating the transition to net zero requires significant collaboration and shared responsibility between the private and public sectors. We believe that business commitments to climate action backed by private sector actions and investments can reinforce the mandate for governments to raise their own ambitions and enable faster progress.Government targets, supporting policies and transition plans can provide clarity, predictability and the competitive landscape to encourage more businesses to take action and to make transition-aligned investments.
As members of the Alliance of CEO Climate Leaders, we have committed to reducing emissions by more than 1 gigatons annually by 2030 and have, on average, reduced scope 1 and 2 emissions by 22% from 2019-2020 levels, outpacing major nations.*
We call on our peers in the private sector to join us in:
Setting science-based targets in line with the Paris Agreement, with a clear roadmap that takes sector-specific pathways into account.
Collaborating within and across sectors and value chains to drive transparency, advocacy and action in alliances and initiatives while working with major industry and trade associations to advance alignment with the Paris Agreement.
Contributing to the development of internationally harmonized reporting standards.
In this context and with leaders meeting at COP27 and the G20, we call on governments to:
Set bold ambitions and follow through on commitments
Deliver on the promise in the Glasgow Climate Pact and commit to ambitious and Paris Agreement-aligned nationally determined contributions and translate them into plans and policies that at least halve global carbon emissions by 2030 and contribute to global net zero by 2050.
Accelerate the transition
Drive down the green premium of low-carbon technologies for hard-to-abate sectors by unlocking blended finance (concessionary lending, guarantee mechanisms and others), scaling innovative sustainable finance mechanisms, integrating climate and sustainability criteria in public procurement and promoting the alignment of international standards for transformational technologies.
The focus is on action. Recognizing that many solutions already exist, there is an urgent need to:
Break down barriers by simplifying regulations, speeding up permitting processes and creating the enabling policy frameworks to accelerate scaling and deploying these solutions. Essential to progress is increased R&D expenditure and the inclusion of digital and physical infrastructure to ensure supply meets demand.
Provide incentives, including policies for emerging renewable energy and energy efficiency technologies on both the supply and the demand side, while also supporting hard-to-abate sectors through additional funding for innovation and the scaling up of new solutions, including circularity, carbon removal and natural climate solutions.
Put a price on carbon and phase out fossil fuel subsidies in a way that is both just and results in their eventual elimination. Combined, this will improve the competitiveness of sustainable low-carbon technologies.
Invest in reskilling and upskilling of those in the workforce that are impacted by the transition and enable more people to participate in the green economy.
Invest in mitigation, adaptation, and a just transition
Ensure that developed countries meet and exceed their $100 billion commitment and that these funds go directly to supporting developing countries’ efforts to mitigate and adapt to climate change. This is fundamental to establishing and maintaining confidence between countries to tackle the climate crisis together.
The impacts of climate change are already being felt, from more frequent heatwaves and wildfires to more severe tropical cyclones and floods. These changes disproportionately impact developing countries and threaten current and future economic development, human health and welfare. For new climate adaptation infrastructure projects, governments should strive for a conditionality of sustainability (e.g. building materials and techniques). Investing in water, healthy food systems and resilient supply chains while increasing local production in the Global South using regenerative agriculture and other sustainable farming and food production practices is integral to climate adaptation and resilience.
This must be done while protecting biodiversity and ecosystems and ensuring a fair and inclusive transition for all. This transition needs a radical rethinking of how we do business and a prolonged focus throughout the private and public sectors aligned with bold policy actions to decarbonize the economy.
Internationally harmonize reporting and disclosure standards
With the current divergence of standards underway, we call on the International Sustainability Standards Board (ISSB), the European Commission, the U.S. Securities and Exchange Commission (SEC) and all other regulating bodies to align their collective efforts to arrive at globally-aligned standards to accurately measure and compare progress against ambitious targets. The standards must be interoperable, decision-useful and implementable to ensure they create trust and lasting change. Finally, market-based instruments (including carbon markets, power purchase agreements, etc.) have an essential role to play in reducing carbon emissions globally but need greater alignment and clear standards and frameworks.
This is the decade of action, so we must work side-by-side with governments to scale up public-private efforts in the drive to net zero. Alliance members will be in Egypt during COP27 to discuss with world leaders, government officials and civil society representatives how, together, we can take positive action to tackle the climate crisis.
99. Svein Tore Holsether, President and Chief Executive Officer, Yara International ASA
100. Wolf-Henning Scheider, Chairman of the Board of Management and Chief Executive Officer, ZF Group
101. Mario Greco, Group Chief Executive Officer, Zurich Insurance Group
*Such as Brazil (13% 2019-2020 reduction), USA (11% 2019-2020 reduction), Europe and India (both 8% 19-20 reduction), all taken from the Carbon Monitor Programme, Nature.com analysis.
Original source: World Economic Forum (Public License)
Marshland in Holden Beach, USA, likely to have prevented storms and surges from having a worse impact in North Carolina. Photo by Steve Adams on Unsplash
By David L. Chandler, World Economic Forum (Public License).
Coastal marsh plants provide significant protection from surges and devastating storms.
Research in MIT’s Parson’s lab can help coastal planners to take important details into account when planning projects.
Countries must take advantage of this modeling in order to restore marshland with specific plants in certain areas.
Marsh plants, which are ubiquitous along the world’s shorelines, can play a major role in mitigating the damage to coastlines as sea levels rise and storm surges increase. Now, a new MIT study provides greater detail about how these protective benefits work under real-world conditions shaped by waves and currents.
The study combined laboratory experiments using simulated plants in a large wave tank along with mathematical modeling. It appears in the journal Physical Review — Fluids, in a paper by former MIT visiting doctoral student Xiaoxia Zhang, now a postdoc at Dalian University of Technology, and professor of civil and environmental engineering Heidi Nepf.
“After a few years, the marsh grasses start to trap and hold the sediment, and the elevation gets higher and higher, which might keep up with sea level rise.”
—Xiaoxia Zhang, now a postdoc at Dalian University of Technology, and professor of civil and environmental engineering Heidi Nepf
A new MIT study provides greater detail about how thes protective benefits of marsh plants work under real-world conditions shaped by waves and currents. The simulated plants used in lab experiments were designed based on Spartina alterniflora, which is a common coastal marsh plant. Credit: Xiaoxia Zhang.
It’s already clear that coastal marsh plants provide significant protection from surges and devastating storms. For example, it has been estimated that the damage caused by Hurricane Sandy was reduced by $625 million thanks to the damping of wave energy provided by extensive areas of marsh along the affected coasts. But the new MIT analysis incorporates details of plant morphology, such as the number and spacing of flexible leaves versus stiffer stems, and the complex interactions of currents and waves that may be coming from different directions.
This level of detail could enable coastal restoration planners to determine the area of marsh needed to mitigate expected amounts of storm surge or sea-level rise, and to decide which types of plants to introduce to maximize protection.
“When you go to a marsh, you often will see that the plants are arranged in zones,” says Nepf, who is the Donald and Martha Harleman Professor of Civil and Environmental Engineering. “Along the edge, you tend to have plants that are more flexible, because they are using their flexibility to reduce the wave forces they feel. In the next zone, the plants are a little more rigid and have a bit more leaves.”
As the zones progress, the plants become stiffer, leafier, and more effective at absorbing wave energy thanks to their greater leaf area. The new modeling done in this research, which incorporated work with simulated plants in the 24-meter-long wave tank at MIT’s Parsons Lab, can enable coastal planners to take these kinds of details into account when planning protection, mitigation, or restoration projects.
“If you put the stiffest plants at the edge, they might not survive, because they’re feeling very high wave forces. By describing why Mother Nature organizes plants in this way, we can hopefully design a more sustainable restoration,” Nepf says.
Once established, the marsh plants provide a positive feedback cycle that helps to not only stabilize but also build up these delicate coastal lands, Zhang says. “After a few years, the marsh grasses start to trap and hold the sediment, and the elevation gets higher and higher, which might keep up with sea level rise,” she says.
Awareness of the protective effects of marshland has been growing, Nepf says. For example, the Netherlands has been restoring lost marshland outside the dikes that surround much of the nation’s agricultural land, finding that the marsh can protect the dikes from erosion; the marsh and dikes work together much more effectively than the dikes alone at preventing flooding.
But most such efforts so far have been largely empirical, trial-and-error plans, Nepf says. Now, they could take advantage of this modeling to know just how much marshland with what types of plants would be needed to provide the desired level of protection.
It also provides a more quantitative way to estimate the value provided by marshes, she says. “It could allow you to more accurately say, ‘40 meters of marsh will reduce waves this much and therefore will reduce overtopping of your levee by this much.’ Someone could use that to say, ‘I’m going to save this much money over the next 10 years if I reduce flooding by maintaining this marsh.’ It might help generate some political motivation for restoration efforts.”
Nepf herself is already trying to get some of these findings included in coastal planning processes. She serves on a practitioner panel led by Chris Esposito of the Water Institute of the Gulf, which serves the storm-battered Louisiana coastline. “We’d like to get this work into the coatal simulations that are used for large-scale restoration and coastal planning,” she says.
This photo shows examples of Spartina alterniflora in China. Credit: Xiaoxia Zhang.
“Understanding the wave damping process in real vegetation wetlands is of critical value, as it is needed in the assessment of the coastal defense value of these wetlands,” says Zhan Hu, an associate professor of marine sciences at Sun Yat-Sen University, who was not associated with this work. “The challenge, however, lies in the quantitative representation of the wave damping process, in which many factors are at play, such as plant flexibility, morphology, and coexisting currents.”
The new study, Hu says, “neatly combines experimental findings and analytical modeling to reveal the impact of each factor in the wave damping process. … Overall, this work is a solid step forward toward a more accurate assessment of wave damping capacity of real coastal wetlands, which is needed for science-based design and management of nature-based coastal protection.”
The work was partly supported by the National Science Foundation and the China Scholarship Council.
