National climate strategies set out how countries plan to reduce emissions, for example by phasing out fossil-fuel use, to get to net-zero in 2050. The study found, once the bulk of emissions have been reduced, countries plan to ‘cancel out’ the left-over difficult to decarbonise emissions, such as those from agriculture, by using forests and soils to remove carbon from the atmosphere.

However, this may prove risky because forests and soils are also threatened by a range of impacts, such as fire, disease, changes in farming practices or deforestation. These mean forests and soils could lose their stored carbon back to the atmosphere.

There is also a risk of being over optimistic about the amount of carbon forests and soils can remove to reach net zero, especially if combined with delays to reducing emissions from coal, oil, and gas.

The findings, published in the journal Communications Earth & Environment, show that most of the strategies submitted to the United Nations Framework Convention on Climate Change (UNFCCC) do not quantify the amount of carbon ‘removals’ needed in 2050.

With progress on reducing emissions stalling at COP27, the researchers call for the reporting requirements on long-term national climate plans to be urgently strengthened.

“The deployment of carbon dioxide removal is essential to reach global and national net-zero emissions targets, but little attention has been paid to its practical deployment by countries,” said the study’s lead author Harry Smith, a Leverhulme Trust Doctoral Scholar in the School of Environmental Sciences and Tyndall Centre for Climate Change Research at UEA.

“Nature-based removals, such as using forests and soils, remain vital to address challenges in biodiversity and climate adaptation, but may be risky if used as the only way to remove carbon. Countries should also explore engineered carbon removal methods. To meet the challenge of net-zero, we need both.”

The study analysed how Carbon Dioxide Removal (CDR) methods — which remove CO₂ from the atmosphere and permanently store it in forests, soils, the oceans, or underground geological formations — are integrated into climate strategies.

It groups the methods into ‘nature-based CDR’, for example storing carbon in forests, soils, or coastal habitats, and ‘engineered-CDR’, storing carbon deep underground through biomass energy with carbon capture and storage or direct air carbon capture and storage.

Despite being central to net-zero ambitions, the research finds CDR is rarely made explicit in policy plans. Some countries such as France look to engineered removals as a possible long-term solution. Others, such as Australia and Latvia, look to the potential of international cooperation and the creation of carbon markets to transfer removals between countries.

Meanwhile the UK is investing in research and development for engineered-CDR and has a near-term 2030 target for the amount of carbon removed by these methods.

Since the adoption of the Paris Agreement in 2015, more than 124 countries have agreed to a net-zero emissions target, defined as a balance of emission sources and anthropogenic removals.

Unlike many studies, which focus on short-term pledges to 2030 published by countries, otherwise known as ‘Nationally Determined Contributions’ or ‘NDCs’, this study focuses on long-term national climate strategies.

Officially called ‘long-term low emission development strategies’ or ‘LT-LEDS’, these often represent modelled scenarios or pathways to 2050 or beyond, providing for greater engagement with CDR than NDCs.

“Long-term national climate strategies are an important tool to think through carbon dioxide removal at the national level and we advocate that they should be made compulsory under the UNFCCC, as opposed to their current optional status,” said Mr Smith.

The study examined 41 LT-LEDS submitted to the UNFCCC before the start of 2022, capturing those published in and around COP26 — and totalling 3,885 pages — to determine how countries quantify and discuss CDR. The analysed strategies are mostly from the Global North and cover 58% of global 2019 greenhouse gas emissions and around 74% of global GDP.

The findings show that enhancing forest and soil carbon sinks are the most advocated strategies but are only explicitly quantified in 12. Remaining difficult to decarbonise emissions by 2050 are only quantified in 20 strategies and most of them use forests to achieve national net-zero targets.

Strategies that quantify both the remaining difficult to decarbonise emissions and carbon dioxide removal identify national constraints, such as wildfire risks to forests and limited geological CO₂ storage capacity. Strategies also highlight the need for international cooperation.

Co-author Dr Naomi Vaughan, Associate Professor in Climate Change at UEA, said: “With more countries submitting long-term national climate strategies during COP27, the UNFCCC should urgently strengthen its reporting requirements.

“Carbon dioxide removal is an important part, together with reducing emissions, of how countries will reach net zero. National level analysis is needed to determine how countries plan on incentivising different CDR methods.

“This combines with an urgent need to scale-up efforts to reduce emissions and develop CDR methods to meet the scales needed to reach Paris Agreement temperature targets.”

Using computer models, the team, led by Panos Georgopoulos, a professor of Environmental and Occupational Health and Justice at the Rutgers School of Public Health, found that by 2050 climate change significantly will increase airborne pollen loads, with some of the largest surges occurring in areas where pollen is historically uncommon.

“Pollen is an excellent sentinel for the impacts of climate change because shifts in variables like carbon dioxide and temperature affect the way plants behave,” said Georgopoulos, who also is director of the Computational Chemodynamics Laboratory at Rutgers and faculty at Robert Wood Johnson Medical School. “At the same time, the production of pollen and pollen’s influence on allergic disease has been increasing due to climate change, and this is one of few studies to forecast this trend into the future.”

Previous efforts to connect pollen indices with climate change have been limited by a scarcity of data. For instance, there are about 80 pollen sampling stations in the U.S., operated by a variety of private and public agencies using different sampling methods.

To overcome this challenge, the researchers adapted the Community Multiscale Air Quality modeling system, an open-source tool managed by the U.S. Environmental Protection Agency (EPA) to simulate distributions of allergenic oak and ragweed pollen for historical (2004) and future (2047) conditions.

Results showed that even under moderate warming conditions, pollen season will start earlier and last longer throughout the U.S., with increasing average pollen concentrations in most parts of the nation. Mean concentrations of oak pollen could climb by more than 40 percent in the Northeast and Southwest and mean concentrations of ragweed could jump by more than 20 percent in these areas.

Regional pollen shifts were observed, too. In parts of Nevada and northern Texas, oak pollen levels could double by mid-century, while Massachusetts and Virginia could see an 80 percent increase in ragweed pollen by 2050.

The pollen research was part of an ongoing project by the Rutgers Ozone Research Center, which is funded by the EPA and New Jersey to study how climate change will influence air quality in the state. The bulk of that work examines the state’s struggles with ground level ozone, a byproduct of fossil fuel combustion that can damage the lungs.

“New Jersey’s air quality is going to be adversely impacted by climate change, both in terms of anthropogenic pollution and increased levels of pollen,” Georgopoulos said. “For people with asthma, exposure to pollen and irritants like ozone increases the odds of respiratory illness. To protect the most vulnerable, we need to understand how these irritants will behave in a warming world.”

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Materials provided by Rutgers University. Original written by Greg Bruno. Note: Content may be edited for style and length.

The study, led by civil and environmental engineering professor and Prairie Research Institute executive director Praveen Kumar, evaluated 14 water-stressed locations across the globe for the feasibility of a hypothetical structure capable of capturing water vapor from above the ocean and condensing it into fresh water — and do so in a manner that will remain feasible in the face of continued climate change.

Kumar, graduate student Afeefa Rahman and atmospheric sciences professor Francina Dominguez published their findings in the journal Nature Scientific Reports.

“Water scarcity is a global problem and hits close to home here in the U.S. regarding the sinking water levels in the Colorado River basin, which affects the whole Western U.S.,” Kumar said. “However, in subtropical regions, like the Western U.S., nearby oceans are continuously evaporating water because there is enough solar radiation due to the very little cloud coverage throughout the year.”

Previous wastewater recycling, cloud seeding and desalination techniques have met only limited success, the researchers said. Though deployed in some areas across the globe, desalination plants face sustainability issues because of the brine and heavy metal-laden wastewater produced — so much so that California has recently rejected measures to add new desalination plants.

“Eventually, we will need to find a way to increase the supply of fresh water as conservation and recycled water from existing sources, albeit essential, will not be sufficient to meet human needs. We think our newly proposed method can do that at large scales,” Kumar said.

The researchers performed atmospheric and economic analyses of the placement of hypothetical offshore structures 210 meters in width and 100 meters in height.

Through their analyses, the researchers concluded that capturing moisture over ocean surfaces is feasible for many water-stressed regions worldwide. The estimated water yield of the proposed structures could provide fresh water for large population centers in the subtropics.

One of the more robust projections of climate change is that dry regions will get drier, and wet areas will get wetter. “The current regions experiencing water scarcity will likely be even drier in the future, exacerbating the problem,” Dominguez said. “And unfortunately, people continue moving to water-limited areas, like the Southwestern U.S.”

However, this projection of increasingly arid conditions favors the new ocean vapor-harvesting technology.

“The climate projections show that the oceanic vapor flux will only increase over time, providing even more fresh water supply,” Rahman said. “So, the idea we are proposing will be feasible under climate change. This provides a much needed and effective approach for adaptation to climate change, particularly to vulnerable populations living in arid and semi-arid regions of the world.”

The researchers said one of the more elegant features of this proposed solution is that it works like the natural water cycle.

“The difference is that we can guide where the evaporated water from the ocean goes,” Dominguez said. “When Praveen approached me with this idea, we both wondered why nobody had thought about it before because it seemed like such an obvious solution. But it hasn’t been done before, and I think it is because researchers are so focused on land-based solutions — but our study shows other options do, in fact, exist.”

The researchers said this study opens the door for novel infrastructure investments that can effectively address the increasing global scarcity of fresh water.

The University of Illinois Urbana-Champaign, the Lovell Professorship in the department of civil and environmental engineering, The University Scholar Program and the National Science Foundation supported this research.

Researchers at the University of Bern have now developed a new method to determine the necessary reduction in emissions on a continuous basis. The main idea: Instead of complex climate models and scenarios, the observed relationship between warming and emissions is applied, and the reduction path is adapted repeatedly according to the latest observations. This new approach has just been published in the journal Nature Climate Change.

A new calculation method for the emission reduction path

To date, climate models have been used to calculate possible emissions pathways to the net zero goal. These pathways are based on scenarios including economic and social developments. “These calculations for the emission paths are subject to large uncertainties. This makes the decision-making more difficult and might be one reason why the promised reductions made by the 194 signatory countries to the Paris Agreement remain insufficient,” says lead author Jens Terhaar, explaining the background to the study. Like most of the other authors, Terhaar is a member of the Oeschger Center for Climate Change Research at the University of Bern.

“Since the climate agreement actually aims at regulating temperature, we thought to specify an optimal emissions reduction path for this purpose which is independent of model-based projections,” continues Terhaar. According to this initial idea, a calculation method has emerged which is based exclusively on observation data: on the one hand, global surface temperatures in the past, and on the other hand, CO2 emissions statistics.

The Paris Agreement calls for a stocktake of the necessary reductions in global emissions every five years. “The new Bern calculation method is ideally suited to support the stocktake mechanism of the Paris Agreement, as it enables the emission reductions to be recalculated regularly on an adaptive basis,” explains co-author Fortunat Joos of the Oeschger Center. For this purpose, a new algorithm has been developed which is known as the AERA (adaptive emissions reduction approach). In simple terms, the algorithm correlates CO2 emissions with rising temperatures, and is adjusted using a control mechanism. In this way, the current uncertainties in the interaction between these variables can be put aside.

“Our adaptive approach circumvents the uncertainties, so to speak,” explains Fortunat Joos. “In the same way that a thermostat continuously adjusts the heating to the required room temperature, our algorithm adjusts the emission reductions according to the latest temperature and emissions data. This will allow us to approach a temperature goal, such as the 2°C goal, step-by-step and with specific interim goals.”

Stronger emissions goals and effective implementation

“The AERA method already confirms that international climate policy must be far more ambitious,” demands Terhaar. According to the Bern study, to achieve the 2°C goal, global CO2 emissions would have to fall by 7 percent between 2020 and 2025. They actually increased by approximately 1 percent in 2021 in comparison with 2020, though. According to the algorithm, limiting global warming to 1.5°C would require as much as a 27 percent reduction by 2025. “We need far stricter emissions goals than those to which nations have committed,” explains Thomas Frölicher, co-author of the study from the Oeschger Center, “and above all else, effective implementation of the goals.”

The Researchers in Bern hope that the new calculation method will succeed in finding its way into international climate policy. “The AERA algorithm is already attracting a lot of interest in the climate research community, as it can also be applied to climate modelling,” explains Jens Terhaar. Until now, climate models with prescribed greenhouse gas concentrations have been used. This meant that at the end of the 21st century, the warming for a specific greenhouse gas concentration was very uncertain. When using the climate models with the AERA, however, emissions are continuously adjusted according to the calculated temperature and the intended temperature goal. On this basis, the model temperature is eventually stabilised at the intended level and all the models simulate the same warming, but with different emission pathways. “The AERA enables us to study impacts such as heat waves or ocean acidification for different temperature goals — such as 1.5°C versus 2°C versus 3°C — on a consistent basis and with state-of-the-art models,” explains Terhaar.

Worldwide, 11 research groups have already started to apply the algorithm under the leadership of the University of Bern in order to study such impacts.

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Materials provided by University of Bern. Note: Content may be edited for style and length.

There are many reasons why natural gas is the most common home heating source in America while fewer than 10% of U.S. homes burn wood as a primary heat source. If your home is in the wood-burning camp, you already know that fireplaces are not the best home heating system. Fuel availability is often the driving force behind choosing to heat with wood — either because you have your own woodlot, or because heating with electricity or pulling gas to a remote home is prohibitively expensive.

In some cases, wood stoves can be an ecological choice, if you choose your stove wisely and burn your wood properly. Take a few minutes to assess your choices, because some wood-burning options are far better for the environment.

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Stoves vs. Fireplaces

Sometimes people refer to wood stoves and fireplaces interchangeably. They are both hearth appliances (that is, safe containment systems for burning fires) and the fuel they both burn is generally wood. Sometimes they even look the same when wood stoves are placed inside a fireplace structure.

But there is a world of difference between the two. A fireplace is essentially an indoor campfire. At best, a fireplace achieves about 10% efficiency in its use of the energy stored in the wood. They can even operate at negative efficiency, meaning they actually draw more heat out of the house than they create. By contrast, a wood stove is a fully-enclosed appliance whose efficiency can be up to 50% higher than the fireplace. Wood stoves are rated by the EPA.

Measuring Wood Stove Efficiency

There are two ways of measuring the efficiency of wood-burning appliances.

Combustion efficiency refers to how much of the energy embodied in the fuel is converted to heat (rather than smoke, ash, or other byproducts). Overall efficiency is the percentage of the available energy that is actually transferred to the space to be heated.

Overall efficiency will always be lower than the combustion efficiency — by as much as 20%. So, when you are shopping for a wood stove, be sure to find out which efficiency the number on the tag refers to.

Good Wood

There is no Energy Star system for wood stoves because they generally do not draw electric power. But the EPA has established standards for wood stove efficiency. An EPA certified wood stove is independently tested by an accredited laboratory to meet the New Source Performance Standards (NSPS) emission limits that govern how many particulates a stove can release into the air. Basically, NSPS requires all but a few grams of your wood is completely burned instead of going up the chimney as soot and ash.

In 2020, the NSPS emission limit for new room heaters was lowered to 2.5 grams of particulate per hour burning cordwood. Wood stoves certified under the 2015 NSPS meet a particulate emissions limit of no more than 4.5 grams per hour. So stoves manufactured before 1990 should be replaced, however aesthetically pleasing their design may be, to meet the new standards. They burn wood much less efficiently than contemporary models, wasting fuel and polluting the air inside your home and outdoors.

Currently certified wood stoves produce heat 50% more efficiently, require 30% less wood, decrease pollution by 70% and reduce the risk of creosote buildup compared to older stoves.

Alternate Fuels

Pellet stoves, which burn pellets of compressed sawdust, are still your best choice. They are the cleanest burning solid-fuel stove option.

Some models of EPA-certified pellet stoves can reach efficiencies in the range of 70% to 83% — comparable to a gas fireplace. You do have to buy pellets, which eliminates the savings from cutting your own wood. And some pellet stoves do require a small amount of electricity to operate the hopper that feeds pellets into the fire, which is a drawback if your home frequently loses power. But there is no question that operating a pellet stove is much less work than burning logs.

Choosing a Wood Stove

There are two types of high-efficiency wood stoves. Non-catalytic stoves are more common. They achieve high combustion rates by using firebox insulation and a large baffle to produce a longer, hotter gas flow path; and by introducing pre-heated air through small holes above the fuel in the firebox. Catalytic stoves tend to be more expensive and depend more on correct maintenance by the user. But they produce the long, even output that homeowners want from a heat source. Catalytic stoves pass the smoky exhaust through a coated ceramic honeycomb inside the stove. There, gases and particles in the smoke ignite and burn.

Proper sizing is also critical to choosing the right stove. Small stoves are best for heating individual rooms or for “zone heating.” Big stoves are best for heating the whole home, but only if you have an open-plan home. In homes with numerous rooms, a large stove can cause one area of the home to overheat while the rest remains cold. You can use a BTU calculator to estimate your heating needs, but it’s best to consult a professional who can help match your particular situation to a right-sized hearth appliance.

This article was originally published on February 12, 2021.

The strongest Arctic cyclone ever observed poleward of 70 degrees north latitude struck in January 2022 northeast of Greenland. A new analysis led by the University of Washington shows that while weather forecasts accurately predicted the storm, ice models seriously underestimated its impact on the region’s sea ice.

The study, published in October in the Journal of Geophysical Research-Atmospheres, suggests that existing models underestimate the impact of big waves on ice floes in the Arctic Ocean.

“The loss of sea ice in six days was the biggest change we could find in the historical observations since 1979, and the area of ice lost was 30% greater than the previous record,” said lead author Ed Blanchard-Wrigglesworth, a research assistant professor of atmospheric sciences at the UW. “The ice models did predict some loss, but only about half of what we saw in the real world.”

Accurate sea ice forecasts are important safety tools for Northern communities, mariners and others operating in Arctic waters. The accuracy of forecasts in the Arctic Ocean also has broader effects.

“The skill of a weather forecast in the Arctic affects the skill of weather forecasts in other places,” Blanchard-Wrigglesworth said.

The January 2022 cyclone had the lowest pressure center estimated since satellite records began in 1979 above 70 degrees north. It was an extreme version of a typical winter storm. Climate change doesn’t appear responsible for the cyclone: The researchers didn’t find a trend in the strength of intense Arctic cyclones since 1979, and sea ice area was close to the historical normal for that region before the storm hit.

During the storm, record winds howled over the Arctic Ocean. The waves grew to 8 meters (26 feet) tall in open water and remained surprisingly strong as they traveled through the sea ice. The ice heaved 2 meters (6 feet) up and down near the edge of the pack, and NASA’s ICESat-2 satellite shows that the waves reached as far as 100 kilometers (60 miles) toward the center of the ice pack.

Six days after the storm struck, the sea ice had thinned significantly in the affected waters north of Norway and Russia, in places losing more than half a meter (about 1.5 feet) of thickness.

“It was a monster storm, and the sea ice got pummeled. And the sea ice models didn’t predict that loss, which suggests there are ways we could improve the model physics,” said second author Melinda Webster, a research assistant professor at the University of Alaska Fairbanks. She begins a research position in the new year at the UW Applied Physics Laboratory.

The new analysis shows that the atmospheric heat from the storm had a small effect, meaning some other mechanism was to blame for the ice loss. Possibilities, Blanchard-Wrigglesworth suggests, include sea ice that was thinner before the storm hit than models had estimated; that the storm’s waves broke up ice floes more forcefully than models predicted as they penetrated deep into the ice pack; or that waves churned up deeper, warmer water and brought it into contact with the sea ice, melting the ice from below.

The unexpected ice loss, despite an accurate storm forecast, suggests that this is an area where models could improve. The researchers hope to monitor future storms to pinpoint exactly what led to the dramatic sea ice loss, potentially by placing sensors in the path of a future approaching storm.

While this storm doesn’t appear to be linked to climate change, an increasing amount of open water as sea ice melts is allowing for larger waves that are eroding Arctic coastlines. Those waves, researchers said, could also affect the remaining sea ice pack.

“Going into the future, this is something to keep in mind, that these extreme events might produce these episodes of huge sea ice loss,” Blanchard-Wrigglesworth said.

Other co-authors are Linette Boisvert at NASA, Chelsea Parker at NASA and the University of Maryland and Christopher Horvat at the University of Auckland and Brown University. The research was funded by NASA, the U.S. Navy’s Office of Naval Research and Schmidt Futures.

Video: https://youtu.be/p44XJ6rAP08

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Materials provided by University of Washington. Original written by Hannah Hickey. Note: Content may be edited for style and length.

Some scientists claim that food webs in the oceans have seen very little change over the last 540 million or so years. However, a team of UNLV researchers has revealed that some ancient food webs were actually very different from today.

The study, published in the latest edition of the journal Frontiers in Ecology and Evolution, used fossils to rebuild four different marine food webs from the days when dinosaurs roamed the earth over 65 million years ago. The food webs were also compared to a reconstructed food web from a modern Jamaican reef. The result? The four ancient food webs varied greatly from one another, and the youngest one was not the most similar to today’s Jamaican coral reefs.

Researchers say the findings point to big changes in the structure of marine ecosystems since they first evolved, and that when looking at conservation and restoration plans, damage to these structures over time caused by humans can impact the ability to fix imbalances and ward off extinction of the species living within them.

“Learning how food webs work is very important for conservation because it helps scientists predict how ecosystems will respond to climate change,” said study co-author Carrie Tyler, a marine conservation paleobiologist and assistant professor in the UNLV department of geoscience.

“There is an interconnectedness and dependency between each member, which means when a stressor affects one species, it will ultimately affect the rest of the web,” she said. “If a species is removed from the structure, the function in the food web may no longer be fulfilled because of the missing piece.”

Tyler said this can make it difficult to reintroduce species down the road, as their functions may no longer fit into the structure. “Using paleontology in this way can help us understand what we should be saving and how to save it, giving us another way to look at conservation efforts.”

Added Roxanne Banker, a UNLV postdoctoral researcher working with Tyler: “By studying these structures over time, we can find ways to promote more resilient communities now, and in the future.”

Takeaways

• Climate change and altered ocean ecosystems due to human activity are of increasing concern. “No pristine ecosystems — those unaltered by human activity — are left on the planet,” Tyler said.
• Community stability in ocean ecosystem structures is determined by which species are in it, what role they play in moving energy, how those functions interact with each other, and how strongly the animals at the top of the food chain affect the rest of the food web. Researchers are looking at how these systems respond to crises and whether or not the species and functions can survive these stressors.
• The new UNLV research can help researchers identify long-term effects of biological invasion — such as the introduction of new species and/or predators, as well as other disturbances in the environment — to determine how we can better help ocean ecosystems bounce back from damage.
• By looking at things over a longer time scale, we can develop a more specific understanding of how human activity has affected ecosystems, which can help us approach restoration and conservation efforts more effectively.

The study was supported by funding from the National Science Foundation.

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Materials provided by University of Nevada, Las Vegas. Original written by Erica Corliss, Keyonna Summers. Note: Content may be edited for style and length.