The records of Greenland's ice melt date back to 1948 and nothing in that record compares to what happened in 2019. The amount of ice lost was more than double what it has been any year since 2013. The net ice loss in 2019 clocked in at more than 530 billion metric tons for 2019. To put that in context, that's as if seven Olympic-sized swimming pools were dumped into the ocean every second of the year, according to The Guardian.
The new study, which used NASA satellite data to measure the size of Greenland's ice, found that in July alone, Greenland lost 223 billion tons of ice. That means for that one month, it lost what it normally loses in an entire year, according to The New York Times.
The study was published Thursday in Communications Earth and Environment. It follows a trend of troubling news coming out of Greenland. Another new study published in the same journal found that even if the climate crisis stopped today, Greenland's ice sheet is so diminished it will never recover, as EcoWatch reported earlier this week. That study found the ice is retreating in rapid bursts and may portend an ominous revision of predictions of sea level rise.
This new study also spells trouble for coastal cities as it may force scientists to revise their predictions to match the accelerated pace of ice melt, as Reuters reported. The island's ice sheet holds enough water to raise sea levels by 20 feet, or six meters, if it were to melt away completely.
"We are likely on the path of accelerated sea level rise," said Ingo Sasgen, a glaciologist at the Alfred Wegener Institute for Polar and Marine Research and co-author of the study, to Reuters. "More melting of the ice sheet is not compensated by periods when we have extreme snowfall.
"What this shows is that the ice sheet is not only out of balance but it's increasingly likely to produce more and more extreme loss years," he added, as CNN reported.
Sasgen noted that 2010 and 2012 were also years with massive amounts of melting and he expects more are in the not-too-distant future.
"The real message is that the ice sheet is strongly out of balance," Sasgen said, as The Guardian reported. "If we look at the record melt years, the top five occurred in the last 10 years, and that is a concern. But we know what to do about it: reduce CO2 emissions."
Greenland's ice sheet is the second largest in the world, behind Antarctica's. CNN notes that the amount of ice it loses everywhere will start to increase sea level beyond the one millimeter it adds annually, pointing out that planet-heating greenhouse gas emissions are the culprit. And all that warming is creating a dangerous feedback loop.
"This extreme melt kicks off feedbacks that may accelerate the mass loss. This is what is worrying, the extremes are increasing and we understand too little about how the ice sheet will respond to more extreme climate variability," Sasgen said, as CNN reported.
The amount of melting that's happening means trouble for the hundreds of millions of people that live along coastlines, but there is still time for them to retreat inland. The ice sheet will likely not melt entirely since the rate of melt tends to slow down as the ice retreats from warmer ocean waters. Furthermore, the centuries it will take to melt completely gives us some time to reverse course on emissions, according to The Guardian.
"If we reduce CO2, we will reduce Arctic warming and we will therefore also reduce the sea level rise contribution from the Greenland ice sheet," Sasgen said, as The Guardian reported. "So even though it might eventually disappear in large part, it happens much slower, which would be better as it would allow more time for the 600 million people living near coasts to move away."
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- Earth Has Lost Over 30 Trillion Tons of Ice in Under 30 Years, Scientists 'Stunned' by Landmark Study - EcoWatch ›
By Kenny Stancil
Over the past five decades, the Arctic has warmed three times faster than the world as a whole, leading to rapid and widespread melting of ice and other far-reaching consequences that are important not only to local communities and ecosystems but to the fate of life on planet Earth.
The Arctic Monitoring and Assessment Program (AMAP) issued that warning on Thursday in a new report that summarizes the latest findings on Arctic change and projections of future transformations under different climate scenarios. The publication of AMAP's report coincides with this week's meeting of the Arctic Council in Reykjavík, Iceland, which brings together policymakers from countries bordering the region.
According to the report, the Arctic's annual mean surface temperature surged by 3.1ºC between 1971 and 2019, compared with a 1ºC rise in the global average during the same time period. Arctic warming has been accompanied by a decrease in snow cover and sea and land ice; an increase in permafrost thaw and rainfall; and an uptick in extreme events.
"The Arctic is a real hotspot for climate warming," Jason Box, a glaciologist at the Geological Survey of Denmark and Greenland, told Agence France-Presse on Thursday.
The rapid warming of the Arctic is releasing significant amounts of carbon dioxide and methane, accelerating the… https://t.co/L50di68FYG— Environmental Justice Foundation (@Environmental Justice Foundation)1621440072.0
AMAP stressed that the current transformation of the Arctic environment is adversely affecting the livelihoods and food security of Arctic communities, especially Indigenous ones. Arctic warming also poses risks to unique terrestrial, coastal, and marine ecosystems in the region, some of which are vulnerable to irreversible harm. Moreover, the report emphasized, "changes in the Arctic have global implications," especially if potentially negative feedback loops are triggered.
"No one on Earth is immune to Arctic warming," the report said. "The rapid mass loss of the Greenland ice sheet and other Arctic land ice contributes more to global sea-level rise than does the melting of ice in Antarctica."
Some projections estimate that by 2050, 150 million people worldwide will be displaced from their homes just by rising sea levels.
Without an adequate international effort to slash greenhouse gas (GHG) emissions, that number could be far higher.
According to the report, the latest climate models indicate that "annual mean surface air temperatures in the Arctic will rise to 3.3–10°C above the 1985–2014 average by 2100, depending on the course of future emissions."
"Under most emission scenarios," the report said, "the vast majority" of climate models "project the first instance of a largely sea-ice-free Arctic in September occurring before 2050," and possibly as early as 2040.
Because each fraction of a degree of warming makes a difference, the stakes for adequate climate action are immense.
If the global temperature rises to 2°C above pre-industrial levels, the report pointed out, an ice-free Arctic summer is 10 times more likely than if planetary heating is limited to 1.5ºC, the more ambitious target of the Paris agreement.
A growing number of countries, including major economies like the United States and the European Union, have recently pledged to cut GHG emissions by at least 50% below 2005 levels by the end of this decade on the way to net-zero by midcentury.
Reposted with permission from Common Dreams.
- Rewilding the Arctic Could Slow the Climate Crisis - EcoWatch ›
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Whether you're installing a DIY solar panel system or having a top solar company handle the details, you'll want to choose the best solar panels for your home. But with so many options, it can be hard to know which panels you need.
In this article, we'll narrow down the 10 best residential solar panels based on materials, price, efficiency and more. All homes are different, so there's no one best solar panel for every system. It's important for homeowners to assess their specific needs and to select the right solar panels to accommodate their household energy requirements.
Each product featured here has been independently selected by the writer. If you make a purchase using the links included, we may earn commission.
Our Top Solar Panels for 2021
For those who wish to take advantage of solar power, the first step is assembling a solar system for home use. This system will generally include a battery, an inverter and of course an array of solar panels. Based on factors such as efficiency, durability, warranty, price point and temperature coefficient, these are the 10 best solar panels for home use:
- LG: Best Overall
- SunPower: Most Efficient
- Panasonic: Best by Temperature Coefficient
- Silfab: Best Warranty
- Canadian Solar: Most Affordable
- Trina Solar: Best Value
- Q Cells: Consumer Favorite
- Mission Solar: Best Small Manufacturer
- Loom Solar: Most Reliable
- WindyNation: Best for Backup Power
As you can see, each of these solar panels excels in a certain area, and each one comes with its own pros and cons. Again, as you seek the best residential solar panels, it's crucial to consider the specific needs of your home and your solar power system.
How We Ranked the Best Solar Panels
In choosing our rankings, we carefully researched many types of solar panels from the industry's top manufacturers, evaluating them according to several criteria. Some of the factors we used to arrive at our rankings include:
The efficiency rating of a solar panel refers to the amount of captured sunlight that it can actually convert into useful energy. Keep in mind that solar panel efficiency tops out just over 20%, and generally speaking, the most efficient solar panels will yield the greatest energy savings for your home.
Solar panels represent a significant investment, and naturally, homeowners want to select products that are going to hold up over time. This means you'll want to buy solar panels that are made to be durable, and to withstand even intense weather.
A good, strong performance warranty can give peace of mind after you purchase residential solar panels. In this industry, a decent warranty may be anywhere from 10 years to 25.
Naturally, you will want to consider your budget before investing in solar panels. The cost of solar panels can fluctuate based on many factors. As you think about a panel's price tag, however, also factor in things like durability and warranty, which provide you a fuller sense of overall value.
Another important ranking factor is temperature coefficient. With solar panels, temperature coefficient refers to how much (or how little) the panel's productivity is diminished when the external temperature rises. How solar panels work in extreme heat plays a key role in year-round power output.
10 Best Solar Panels for Home
Based on the criteria outlined above, these are our picks for the top 10 best solar panels available in 2021.
1) Best Overall: LG
For our top selection, and our vote for all-around best residential solar panel, we're going with LG. LG is a top-tier electronics company, and its solar panels are known for their quality and durability. Truly, these are premium products that work well with almost any home solar configuration.
A quick look at LG's technical stats confirms this. In terms of efficiency, LG solar panels are almost unbeatable. (They are rated as 22% efficient; the only brand we've found that can surpass that is SunPower, and by less than a full percentage point.) A competitive price point and robust 25-year warranty just sweeten the deal and make LG the most recommendable of home solar panels.
2) Most Efficient: SunPower
If you're buying residential solar panels based solely on their efficiency, SunPower is the name to beat. (Remember, efficiency refers to the amount of sunlight that the panels can absorb and turn into useful energy for your home.) SunPower has the highest efficiency we've seen from any solar panel: 22.8%. And on top of that, we'll note that SunPower is reasonably priced and comes with a decent product warranty.
The bottom line: If you're mainly looking for a powerhouse, SunPower is definitely a solar panel manufacturer for you to consider.
3) Best by Temperature Coefficient: Panasonic
Panasonic is our choice for the solar panel with the best temperature coefficient. Basically, that means it will continue to perform at a peak output even when the external temperature rises. For those who live in extremely warm climates, this is an important consideration. (As for technical specs, note that the temperature coefficient rating for the Panasonic solar panel is -0.26.)
Beyond that, this is another example of a well-made product by a top-tier electronics company, and we think homeowners will love it for its durability and its overall quality.
4) Best Warranty: Silfab
When it comes to solar panels, the typical warranty may be anywhere from 10 years to 25 years. There are actually a number of products that hit that 25-year mark, including some that we've mentioned already, but we'll give the honor to Silfab. Not only does this solar panel come supported by a robust warranty, but it routinely wins accolades for longevity and for overall customer satisfaction.
Silfab is a less prominent name in the solar energy space, but it really deserves your attention. It's a great product that offers tremendous value and is one of our top picks for best solar panels for home use.
5) Most Affordable: Canadian Solar
If you're looking to secure some decent solar panels for a lower price point, Canadian solar may be your best option. This company makes high-quality panels that are not too far off from the industry leaders with regard to efficiency, temperature coefficient and other technical considerations. However, Canadian Solar makes its panels available at a much cheaper price.
One caveat: The warranty for Canadian Solar panels is 12 years, which is reasonable, but certainly a far cry from the industry-leading 25 years. With that one quibble, though, we believe Canadian Solar represents one of the best overall values for home solar panels.
6) Best Value: Trina Solar
Speaking of value, we also want to mention the residential solar panels from Trina Solar.
Trina Solar is a Chinese company, and like Canadian Solar, it does an admirable job of producing premium-quality cell technology at competitive price points. Their panels are almost as cheap as the ones from Canadian Solar, and come with a comparable 12-year warranty. They may actually be just a tad more durable, which is why we rank them as a slightly better value overall. Keep this brand in mind as you seek the best use of your solar dollar.
7) Consumer Favorite: Q Cells
As we considered the best solar panels on the market today, we took into account consumer reviews. Basically, we wanted to get a sense of how actual homeowners rank the leading products. The results were somewhat surprising: Based on reviews from a number of different websites, we found that a smaller company called Q Cells consistently rose to the top.
In terms of sheer customer satisfaction, this may be the company to beat… and of course, Q Cells also offers excellent efficiency, value, durability, and more.
8) Best Small Manufacturer: Mission Solar
The residential solar space is dominated by big tech and electronics companies like LG, Panasonic and even Tesla. For some homeowners, though, there's something appealing about going with a smaller, more niche brand. And if that's the boat you're in, then we're happy to recommend Mission Solar.
These panels are made in the San Antonio, Texas, area, which makes them some of the best U.S.-made products in the solar field. The technical specs are all on point, and the company pulls some robust customer satisfaction numbers, too. Keep Mission Solar on your radar as you seek the best solar panels for home use.
9) Most Reliable: Loom Solar
Buying solar panels is going to require a significant investment, even if you opt for some of the cheaper options. Naturally, you'll want to select robust technology that will withstand the test of time, and also hold up well in extreme elements.
Loom Solar panels are well-regarded for their ruggedness and durability. They are carefully designed to perform well even in intense storms. What's more, they are calibrated to run well even in low light or under cloud coverage.
As you seek solar panels that have a long lifespan and will work well no matter the weather, Loom Solar is a company to keep in mind.
10) Best for Backup Power: Windy Nation
Windy Nation makes panels that are a bit smaller and less robust, so you may not wish to use them as your primary energy source. However, they work extremely well for backup power options, and are also great for powering your RV or your cabin with renewable energy.
We'll also note that, for their size, Windy Nation panels are quite efficient. And, they come backed by a 25-year warranty, which should instill some confidence as you buy.
Free Quote: See How Much You Can Save on the Best Solar Panels
How to Choose the Best Home Solar Panels for You
When looking for the best residential solar panels, here are a few tips to ensure you're picking the right products.
The efficiency of your solar panels is going to be one of the key drivers of how much you cave on monthly utility bills and how quickly you recoup your investment. Each solar panel is rated for a particular efficiency level; the industry standard is between 16 to 18%, so anything in that range is going to be pretty decent. We'll note that SunPower's panels, with 22.8% efficiency, represent the highest rating we've come across.
Check Warranty Information
We also recommend comparing a panel's warranty against the industry standard. Hopefully, any solar panels you buy will come with a warranty of 10 years at a minimum. If you find something with a warranty of 25 years, that's ideal.
Compare Price and Efficiency
Something else to keep in mind is that the most efficient solar panels are not always the most affordable. In some cases, opting for a slightly less efficient product will actually provide superior value. You'll also want to think about the cost of solar panel installation and additional parts such as inverters and battery banks when setting your solar budget.
Think About Your Home Energy Needs
In assessing your solar needs, think about things like your roof's exposure to the sun, the surface area available on your roof and the amount of energy your household consumes on a monthly basis. These factors are all important in determining the number of solar panels you need, as well as the type of solar panels.
What Are the Different Types of Solar Panels?
When shopping for residential solar panels, it's also helpful to know the basic types that are available. The three basic categories are monocrystalline, polycrystalline and thin-film. Each type of solar panel comes with its own list of pros and cons.
Monocrystalline: Monocrystalline panels are made from a single, pure crystal of silicon. This allows them to have higher efficiency levels, but they also tend to be more expensive due to a more costly manufacturing process. Note: If you have less space on your roof and can only fit a small number of panels, monocrystalline solar panels may be the only viable option.
Polycrystalline: Polycrystalline solar panels are also made of silicon, but in this case, they are assembled from smaller fragments. This means they are often a little less efficient than monocrystalline panels, but they are also a more affordable option.
Thin-Film: Finally, thin-film solar panels can be made from a variety of ultra-thin materials. Thin-film panels are recommended when you need something that's lightweight, flexible and portable; they may work better for RVs and campsites than for homes. Thin-film panels can be relatively low in efficiency when compared to the other two options.
Do Solar Panels Require Maintenance?
When weighing solar energy pros and cons before making an investment, one of the most common questions that homeowners have is whether their solar panels will require maintenance.
For the most part, all the hard work comes on the front end. Installing a home solar system requires in-depth knowledge of electronics as well as solar power, and in most cases, a solar installation will take a few days. We recommend outsourcing this to trained solar professionals.
Once your system is in place, however, the level of upkeep required is extremely minimal. You will likely have little or no issue with your solar panels for 20 to 30 years. And if you do run into an issue, your warranty will hopefully cover it.
What Impacts Solar Panel Performance?
Solar panels can vary quite a bit in their overall performance and productivity. There are a number of specific factors that can impact how your residential solar system performs, including:
- Orientation: When your solar system is designed, your installer will be careful to position each panel in a way that maximizes its exposure to sunlight. If the orientation is even a little bit off, it can compromise the efficiency of your entire system.
- Weather and sun exposure: If you live in a part of the country that doesn't get consistent sunlight, or if your solar panels are often under cloud coverage, you're not going to produce as much clean energy for your home. (There is a reason why solar panels are especially popular in the Sun Belt.)
- Cleanliness: While solar panels are fairly low maintenance, you may occasionally need to wipe them down, especially in the aftermath of an intense storm. If panels become covered with grime or debris, they may not be able to absorb as much sunlight.
- Shade: Keep in mind that any shade cast over your roof is going to impact the efficiency of your solar panels. If your house is surrounded by tall trees, for example, that could impede solar production.
Bottom Line: Are Solar Panels Worth it for Your Home?
As more and more homeowners seek clean energy solutions, solar power is increasingly attractive. By harnessing the sun's natural rays, homeowners can reduce their dependence on traditional utility companies. Not only does this yield significant savings on monthly electric bills (potentially even eliminating those bills altogether), but it also reduces direct contributions to atmospheric pollution.
Ultimately, the decision about getting solar panels is a highly individual one. For some homeowners, going solar makes plenty of sense. For others, it may prove unwise or unfruitful.
As you consider what's best for you, make sure you take into account your home: The surface area available on your roof, the kind of weather you get, and the level of sunlight you're exposed to.
Also think about the panels themselves: Which performance factors should you consider? Which type of panels is best? And which brand is best aligned with your needs and your budget?
By weighing all of these factors, you can make a well-informed decision about the best solar panels for your household.
Antarctica and Greenland's ice sheets are currently melting at a pace consistent with worst-case-scenario predictions for sea level rise, with serious consequences for coastal communities and the reliability of climate models.
A paper published in Nature Climate Change Monday compared the latest satellite observations of polar ice melt with the predictions outlined in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report. It found that the ice sheets are currently raising sea levels at a rate 45 percent above the IPCC's central prediction and closer to its worst-case scenario. If this continues, the two ice sheets could raise sea levels a further 17 centimeters (approximately 7 inches) more than central predictions by 2100.
"If ice sheet losses continue to track our worst-case climate warming scenarios we should expect an additional 17cm of sea level rise from the ice sheets alone," study coauthor and University of Leeds researcher Anna Hogg said in a university press release. "That's enough to double the frequency of storm-surge flooding in many of the world's largest coastal cities."
Ice sheets losses are tracking the IPCCs worst case climate predictions. This could mean an extra 17 cm of sea leve… https://t.co/wPdqTWef1D— CPOM News (@CPOM News)1598905099.0
Since the 1990s, the two ice sheets have already increased global sea levels by 1.8 centimeters (approximately 0.7 inches). But it was between 2007 and 2017 that the ice sheets began to lose mass at a rate consistent with worst-case-scenario projections, adding around 1.23 centimeters (approximately 0.5 inches) to the water line during that decade, according to the study.
A worst-case-scenario sea level rise as currently predicted would expose 44 to 66 million people to yearly coastal flooding by century's end. But one of study's most alarming implications is that, if sea level rise is already tracking worst-case-scenario predictions, the actual worst-case scenario could be even more dire.
"We need to come up with a new worst-case scenario for the ice sheets because they are already melting at a rate in line with our current one," lead author and Centre for Polar Observation and Modelling (CPOM) at the University of Leeds researcher Thomas Slater told AFP. "Sea level projections are critical in helping governments plan climate policy, mitigation and adaptation strategies. If we underestimate future sea level rise, then these measures may be inadequate and leave coastal communities vulnerable."
One of the reasons climate models might underestimate the worst-case scenario, Slater told AFP, is that they do not account for short-term weather changes such as the heat wave that drove Greenland's record melt in the summer of 2019.
The models that will be used for the IPCC's next report are better at predicting how the ice sheets, oceans and atmosphere interact, Slater said.
The latest study follows a slew of bad news for the world's ice. One study published in August found that the Greenland ice sheet had passed the "point of no return" and would continue to melt even if the climate crisis were halted.
Another recent study, also driven by Leeds' CPOM, calculated that the earth had lost 28 trillion tonnes (approximately 31 trillion U.S. tons) of ice in just 23 years.
These studies reflect a new global reality: In the last five years, melt from ice sheets and glaciers has outpaced the expansion of warming ocean water as the main cause of sea level rise.
"It is not only Antarctica and Greenland that are causing the water to rise," Dr. Ruth Mottram, a coauthor on Monday's study and a climate researcher at the Danish Meteorological Institute, told the University of Leeds. "In recent years, thousands of smaller glaciers have begun to melt or disappear altogether, as we saw with the glacier Ok in Iceland, which was declared 'dead' in 2014. This means that melting of ice has now taken over as the main contributor of sea level rise."
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- Arctic Warming 3x Faster Than Earth's Average Rate, Study Finds ›
The study, published in the journal Communications Earth & Environment Thursday, used more than 30 years of satellite data to determine that the ice sheet would continue to shrink even if surface melting decreased.
However, the findings are not an excuse to give up on climate action.
"We've passed the point of no return but there's obviously more to come," study coauthor and Ohio State University professor Ian Howat told CNN. "Rather than being a single tipping point in which we've gone from a happy ice sheet to a rapidly collapsing ice sheet, it's more of a staircase where we've fallen off the first step but there's many more steps to go down into the pit."
The Greenland ice sheet has reached a point of no return; even if global warming stopped today, the ice sheet will… https://t.co/zDrE58aKc8— Byrd Polar & Climate Research Center (@Byrd Polar & Climate Research Center)1597332307.0
The scientists used monthly data from more than 200 large glaciers that drain into the ocean around Greenland, an Ohio State University press release explained. During the 1980s and 1990s, the glaciers lost roughly as much ice through melt and calving as they gained through snowfall. But, starting in the year 2000, that changed.
"We are measuring the pulse of the ice sheet — how much ice glaciers drain at the edges of the ice sheet — which increases in the summer. And what we see is that it was relatively steady until a big increase in ice discharging to the ocean during a short five- to six-year period," lead study author and Ohio State University Byrd Polar and Climate Research Center scientist Michalea King said in the press release.
Before 2000, the ice sheet had an equal chance of gaining or losing mass each year; now, it only would only gain mass once every 100 years. Greenland's larger glaciers have also retreated about three kilometers (approximately two miles) since 1985. This means more of the glaciers are exposed to warmer ocean water, which increases melting. That is why the ice sheet would continue to retreat if global warming stopped.
Excited to share our new #Greenland paper out today. Our multidecadal, ice sheet-wide study found that an abrupt i… https://t.co/FaskOMwdJU— Michalea King (@Michalea King)1597332609.0
When it comes to climate change, what happens in Greenland does not stay in Greenland. The Greenland ice sheet is the largest contributor to global sea level rise, the paper pointed out. It currently raises ocean levels by more than a millimeter a year, CNN reported. And sea levels are expected to increase by around three feet by century's end.
"There's a lot of places, like in Florida especially, where one meter alone would cover a lot of existing land areas," King told CNN. "And that's exacerbated when you get storms and hurricanes and things like that, that then cause extra surge on top of a higher baseline."
However, King said studies like hers could help low-lying areas adapt to the coming changes.
"The more we know, the better we can prepare," she said in the press release.
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- High Levels of Mercury Found in Greenland's Glaciers ›
By Kimberly M. S. Cartier
As the Arctic continues to warm, climate changes cascade into the marine environment. Top predators like polar bears, beluga whales, and narwhals are affected by shifting seasonality and loss of the Arctic sea ice that shapes where they live and what they eat. Moreover, changes in ocean currents alter the transport of toxins like mercury through Arctic waters, which can create health concerns for top consumers in marine food webs.
Historically, it has been difficult to track how decades of changes in the marine environment have impacted the denizens of the Arctic deep. A recent Current Biology study has shown, however, that the iconic spiral tusks of male narwhals record chemical tracers of diet and mercury exposure over the animals' lifetimes and provide a new paleorecord of the Arctic.
"The tusk is a relatively rare sample to get a hold of … but what's unique about them that is we can do a time trend analysis for each individual," which hasn't been possible before, said Jean-Pierre Desforges, a postdoctoral fellow in marine mammal toxicology at McGill University in Montreal who coauthored the new study. "We don't have that many tusks, but for each tusk we have a lot of data points."
A Change in Diet
Narwhals spend months at a time under Arctic sea ice in remote areas of the world, which can make sample collection very challenging. To date, most data on the impacts of climate change on narwhal come from tissue sampling, which can provide a brief snapshot of an animal's environment. If a researcher wanted to understand these impacts over a narwhal's 50-year life, they'd have to collect tissue samples for 50 years. This limits analysis of trends across a narwhal's lifetime — the samples might come from many animals, or different collection methods might be used. In population-level studies, trends can be overwhelmed by variations among individual animals.
Narwhal tusks provide an alternative. A tusk is an enlarged canine tooth that grows a little bit each year and is connected to the animal's circulatory system. Like whale earplugs, baleen, hair, and teeth, narwhal tusks can be a valuable archive of the animal's environment and habits. A single tusk provides decades' worth of data for a single narwhal. "From the time the animal was killed, we can backtrack through the animal's whole lifetime," Desforges said.
Carbon and nitrogen stable isotopes in the layers of a male narwhal's tusk track whether the animal's food source is from sea ice–dominated waters or open ocean. Rune Dietz
Desforges and his colleagues collected 10 narwhal tusks, each about 1–2.5 meters in length, from animals who lived in the waters off northern Greenland. The team measured stable isotopes of carbon and nitrogen — δ13C and δ15N — as well as mercury levels at multiple points along the length of each tusk, representing growth from 1962 to 2010.
"The carbon isotopes are pretty good trackers of habitat use," Desforges said. "The signals of carbon are very different if you're feeding nearshore or offshore like deep in the ocean, if you're feeding along the sediment at the bottom of the ocean or within the water column…and if you're feeding along the ice-associated food web." Nitrogen isotopes track where on a food web an animal is eating. By combining information from the two isotope signals the team was able to decipher broad trends in the narwhals' diets over their lifetimes.
The tusks revealed that before 1990, the narwhals' diet primarily came from sympagic food webs associated with sea ice, with fish like halibut and Arctic cod. After 1990, narwhals primarily ate open-water (pelagic) food like capelin and armhook squid. This pattern broadly matches observed changes in Arctic sea ice and marine habitats during the study period: Climate-driven changes in the ocean have pushed more pelagic fish into icy Arctic waters, and with less sea ice, narwhals have had to shift where they hunt to better avoid predators like orcas.
Mercury Marks Human Impact
As with δ15N, mercury levels track food web position. In the tusk samples, mercury levels rose with an animal's age and declined as its food source shifted from sympagic prey, which are often at higher trophic levels and have greater bioaccumulation and biomagnification of toxins, to pelagic prey. Temporal trends in the tusks' mercury and nitrogen matched up until 2000, when they sharply diverged.
"The diet suggests that mercury should be going down, whereas the mercury levels rise," Desforges said. "Not only that, they rise a lot faster than they had in the previous decades. So the diet is not the major driver of mercury in recent decades. We propose that [the increase in mercury is associated with] increased global emissions of mercury or else a climate change impact where mercury is becoming more available in the Arctic."
Analyzing more tusks collected in Greenland and elsewhere could help scientists trace where the mercury is coming from and better understand the potential health impacts of mercury on Arctic marine mammals.
Narwhal tusk expert Martin Nweeia, a dental researcher at Case Western Reserve University in Cleveland, Ohio, and Harvard University in Cambridge, Mass., told Nunatsiaq News that insights from tusk samples should be seen as one piece of the puzzle in tracking environmental change. Nweeia, who was not involved with this study, agrees with the researchers that tissue samples and actual stomach contents of tusked and nontusked males and females are needed to see the whole picture. He added that the best way forward would be to work with Inuit and let traditional knowledge guide that work. "I'd be curious what hunters think because they're cutting open stomachs all the time," he said. "They know exactly what that diet is."
The tusks used in this study were provided by Avanersuaq and Uummannaq hunters after traditional subsistence hunts, but "we probably have tusks in museums around the world dating back to who knows when," Desforges noted. "We can get really valuable information if the tusks are in good shape and preserved in the right way. Samples go back in time before the Industrial Revolution, so we could get a good idea of what the prehuman baseline would be for mercury in marine mammals."
This story originally appeared in Eos and is republished here as part of Covering Climate Now, a global journalism collaboration strengthening coverage of the climate story.
The Atlantic Meridional Overturning Circulation (AMOC) helps move heat from the tropics to the Northern Hemisphere, and is one of the reasons why Europe has relatively mild winters, Science Alert explained. However, the current has begun slowing down in recent years, and scientists want to know what it would take for the current to stop. A study published in Proceedings of the National Academy of Sciences Monday calculates that this moment could come sooner than expected.
"It is worrying news. Because if this is true, it reduces our safe operating space," Johannes Lohmann of the Niels Bohr Institute at the University of Copenhagen and study co-author said in a press release.
Essentially, the new findings come down to timing. The AMOC is threatened by increasing freshwater into the North Atlantic as the Greenland ice sheet melts. A certain amount of freshwater will cause the current to stop. But Lohmann wanted to test what would happen if that water were added quickly instead of gradually.
"These tipping points have been shown previously in climate models, where meltwater is very slowly introduced into the ocean," Lohmann told Gizmodo. "In reality, increases in meltwater from Greenland are accelerating and cannot be considered slow."
So researchers used an ocean model called Veros to calculate when the current would stop if freshwater were gradually added, the press release explained. Researchers then added freshwater at increased rates and found that quickly added freshwater would stop currents before reaching the initial freshwater threshold.
This has serious implications for the AMOC current itself. If it were to completely halt, tropical monsoon patterns would shift, rainfall in the Northern Hemisphere would decrease and the North Atlantic would get stormier. It also raises concerns about other climate tipping points, such as polar ice sheets collapsing or the Amazon rainforest drying out. If the AMOC can stop before the previously calculated tipping point is reached, is the same true for other systems?
"The results show that the safe operating space of elements of the Earth system with respect to future emissions might be smaller than previously thought," the study authors wrote.
However, outside scientists urged caution. Dave Sutherland, an associate professor in Earth sciences at the University of Oregon, told Gizmodo that the findings were important and timely, but that the models did not take all details into account, such as the location of the meltwater entering the ocean from Greenland.
Lohmann agreed that more testing is needed, but also pressed the urgency of climate action.
"Due to the potentially increased risk of abrupt climate change in parts of the Earth system that we show in our research, it is important that policymakers keep pushing for ambitious short- and mid-term climate targets to slow down the pace of climate change, especially in vulnerable places like the Arctic," Lohmann told Gizmodo.
By Julia Conley
Ecologists and environmental advocates on Thursday called for swift action to reintroduce species into the wild as scientists at the University of Cambridge in England found that 97% of the planet's land area no longer qualifies as ecologically intact.
"Conservation is simply not enough anymore," said financier and activist Ben Goldsmith. "We need restoration."
Just 3% of world’s ecosystems now remain intact. Conservation is simply not enough anymore. We need restoration. https://t.co/iWcLxAoLWn— Ben Goldsmith (@Ben Goldsmith)1618487636.0
The authors of the study, published in the journal Frontiers in Forests and Global Change, expressed alarm at their findings, which showed that of the 3% of fully intact land, much lies in northern areas which weren't rich in biodiversity to begin with, such as boreal forests in Canada or tundra in Greenland.
The amount of ecologically intact land "was much lower than we were expecting," Dr. Andrew Plumptre, head of the Key Biodiversity Areas Secretariat at Cambridge and lead author of the study, told Science News.
"Going in, I'd guessed that it would be 8 to 10%," he added. "It just shows how huge an impact we've had."
The researchers examined whether natural habitats had retained the number of species which were present in the year 1500—the standard used by the International Union for the Conservation of Nature to assess species' extinction.
Earlier research using satellite imagery led to estimates that 20 to 40% of the planet had retained its natural biodiversity. But areas including dense forests, which can appear intact from above, were found to be missing numerous species.
The researchers linked the loss of unscathed land to hunting and other destructive human activities, disease, and the impact of invasive species. According to The Guardian, the study may underestimate the intact regions because it does not "take account of the impacts of the climate crisis, which is changing the ranges of species."
Only 11% of the land still considered intact was found to be in officially protected areas, but much of the intact regions "coincide with territories managed by indigenous communities, who have played a vital role in maintaining the ecological integrity of these areas," the researchers wrote.
In light of the study, advocates including author George Monbiot and ecologist Alan Watson Featherstone called for "rewilding," or species reintroduction in affected areas.
Rewilding isn't a luxury. It's essential to protect the world's living systems. https://t.co/WbqrTU3VTR— George Monbiot (@George Monbiot)1618465601.0
If anyone wonders why we have a UN Decade on Ecosystem Restoration & rewilding has to become a major focus for huma… https://t.co/7V8IewrqLC— Alan Watson Featherstone (@Alan Watson Featherstone)1618468497.0
The reintroduction of up to five species could help restore 20% of the planet to previous levels of biodiversity, the study found.
"Examples would include reintroducing forest elephants in areas of the Congo Basin where they have been extirpated, or reintroducing some of the large ungulates that have been lost from much of Africa's woodlands and savannas because of overhunting (e.g., buffalo, giraffe, zebras etc.), as long as overhunting has ceased," the researchers wrote.
Previously, the rewilding of gray wolves in Yellowstone National Park in the U.S. led to a resurgence in the park's ecosystem.
Reposted with permission from Common Dreams.
A first-of-its-kind study has examined the satellite record to see how the climate crisis is impacting all of the planet's ice.
The answer? Quite a lot. The rate of worldwide ice loss has increased by more than 60 percent in the past three decades, a study published in The Cryosphere on Monday found.
"The ice sheets are now following the worst-case climate warming scenarios set out by the Intergovernmental Panel on Climate Change," Dr. Thomas Slater, study lead author and research fellow at Leeds' Center for Polar Observation and Modeling, said in a University of Leeds press release. "Sea-level rise on this scale will have very serious impacts on coastal communities this century."
Previous studies have used satellite data to assess ice loss from individual sources, such as polar ice caps, The Guardian explained. However, this is the first one to consider all sources of ice loss. The study found that the world lost around 31 trillion U.S. tons between 1994 and 2017. During that time, the rate of ice loss also increased 65 percent, from 0.9 trillion U.S. tons a year to 1.4 trillion U.S. tons a year. Ice loss from ice sheets in Antarctica and Greenland largely contributed to that number, the press release stated.
The paper also broke down which sources had lost the most ice in total terms between 1994 and 2017. Amounts are approximate and in U.S. tons:
- Arctic sea ice: 8.4 trillion
- Antarctic ice shelves: 7.2 trillion
- Mountain glaciers: 6.7 trillion
- Greenland ice sheet: 4.2 trillion
- Antarctic ice sheet: 2.8 trillion
- Southern Ocean sea ice: one trillion
The study also examined the leading cause of ice melt for each source, according to the press release. For Arctic sea ice and mountain glaciers, rising atmospheric temperatures have driven melting. For the Antarctic ice sheet, rising ocean temperatures have been the main cause. And for the Greenland ice sheet and Antarctic ice shelves, melting has been increased by a combination of the two.
All told, melting from Antarctica, Greenland and mountain glaciers have increased sea levels by around 34.6 millimeters, the study found. While this might not sound like a lot, every centimeter of sea level rise puts around a million people in low-lying areas at risk of being flooded out of their homes, the press release said. Moreover, sea level rise isn't the only threat from melting ice.
"As well as contributing to global mean sea level rise, mountain glaciers are also critical as a freshwater resource for local communities," Inès Otosaka, report co-author and Leeds PhD researcher, said in the press release. "The retreat of glaciers around the world is therefore of crucial importance at both local and global scales."
Melting Arctic sea ice is also a problem because it reduces the ice cover that reflects solar energy back into space.
"As the sea ice shrinks, more solar energy is being absorbed by the oceans and atmosphere, causing the Arctic to warm faster than anywhere else on the planet," Dr. Isobel Lawrence, coauthor and Leeds research fellow, explained in the press release. "Not only is this speeding up sea ice melt, it's also exacerbating the melting of glaciers and ice sheets which causes sea levels to rise."
Climate scientist Gavin Schmidt, who was not involved in the study, called it a "thorough accounting of how ice is disappearing from the Arctic, Antarctic and mountain ranges."
However, he disagreed with the paper's claim that the melting of floating sea ice does not contribute directly to sea level rise. He pointed to a 2007 paper that found that if all currently floating sea ice were to melt, sea levels would rise around four centimeters. Slater agreed that the language should be changed to make it clear that melting floating sea ice does slightly contribute to sea level rise.
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By Jessica Corbett
A new study is shedding light on just how much ice could be lost around Antarctica if the international community fails to urgently rein in planet-heating emissions, bolstering arguments for bolder climate policies.
The study, published Thursday in the journal Geophysical Research Letters, found that over a third of the area of all Antarctic ice shelves — including 67% of area on the Antarctic Peninsula — could be at risk of collapsing if global temperatures soar to 4°C above pre-industrial levels.
An ice shelf, as NASA explains, "is a thick, floating slab of ice that forms where a glacier or ice flows down a coastline." They are found only in Antarctica, Greenland, Canada, and the Russian Arctic—and play a key role in limiting sea level rise.
"Ice shelves are important buffers preventing glaciers on land from flowing freely into the ocean and contributing to sea level rise," explained Ella Gilbert, the study's lead author, in a statement. "When they collapse, it's like a giant cork being removed from a bottle, allowing unimaginable amounts of water from glaciers to pour into the sea."
"We know that when melted ice accumulates on the surface of ice shelves, it can make them fracture and collapse spectacularly," added Gilbert, a research scientist at the University of Reading. "Previous research has given us the bigger picture in terms of predicting Antarctic ice shelf decline, but our new study uses the latest modelling techniques to fill in the finer detail and provide more precise projections."
Check out my piece for @ConversationUK on how & why #Antarctica's #IceShelves are at risk as global #temperatures r… https://t.co/YCMzgfliiR— Dr Ella Gilbert (@Dr Ella Gilbert)1617975049.0
Gilbert and co-author Christoph Kittel of Belgium's University of Liège conclude that limiting global temperature rise to 2°C rather than 4°C would cut the area at risk in half.
"At 1.5°C, just 14% of Antarctica's ice shelf area would be at risk," Gilbert noted in The Conversation.
While the 2015 Paris climate agreement aims to keep temperature rise "well below" 2°C, with a more ambitious 1.5°C target, current emissions reduction plans are dramatically out of line with both goals, according to a United Nations analysis.
Gilbert said Thursday that the findings of their new study "highlight the importance of limiting global temperature increases as set out in the Paris agreement if we are to avoid the worst consequences of climate change, including sea level rise."
"If temperatures continue to rise at current rates," she said, "we may lose more Antarctic ice shelves in the coming decades."
The researchers warn that Larsen C—the largest remaining ice shelf on the Antarctic peninsula—as well as the Shackleton, Pine Island, and Wilkins ice shelves are most at risk under 4°C of warming because of their geography and runoff predictions.
"Limiting warming will not just be good for Antarctica—preserving ice shelves means less global sea level rise, and that's good for us all," Gilbert added.
All the more reason we need to push our leaders towards a quick end to the use of all fossil fuels! https://t.co/yrNUgjbkYG— Food & Water Watch (@Food & Water Watch)1617915642.0
Low-lying coastal areas such as small island nations of Vanuatu and Tuvalu in the South Pacific Ocean face the greatest risk from sea level rise, Gilbert told CNN.
"However, coastal areas all over the world would be vulnerable," she warned, "and countries with fewer resources available to mitigate and adapt to sea level rise will see worse consequences."
Research published in February examining projections from the Fifth Assessment Report of the U.N. Intergovernmental Panel on Climate Change as well as the body's Special Report on the Ocean and Cryosphere in a Changing Climate found that sea level rise forecasts for this century "are on the money when tested against satellite and tide-gauge observations."
A co-author of that study, John Church of the Climate Change Research Center at the University of New South Wales, said at the time that "if we continue with large ongoing emissions as we are at present, we will commit the world to meters of sea level rise over coming centuries."
Parties to the Paris agreement are in the process of updating their emissions reduction commitments—called nationally determined contributions—ahead of November's United Nations climate summit, known as COP26.
Reposted with permission from Common Dreams.
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By Sam Baker
What really makes this reporter's stomach churn thinking about climate change? Thawing permafrost. A scenario where it all melts, releasing copious amounts of CO2 and methane (it holds twice as much carbon as the atmosphere holds right now), and there's no going back.
But what's at the top of the list of concerns for those who study how climate change is unfolding – on ice sheets and urban street corners, in oceans and farm fields – the climate scientists themselves?
DW asked a dozen experts spanning climatology, entomology, oceanography and yes, permafrost research, what keeps them up at night when it comes to the climate.
The Greatest Unknown – People
Nana Ama Browne Klutse studies changing weather with climate models at the University of Ghana. While she says tipping points like permafrost thaw worry her, she also worries how individuals will handle changing climates.
"What can you do as an individual to avoid the impact of climate change?" she asked. "We need government policies for resilience, building of community, city resilience. Then we need that global action."
Climate scientist Ruth Mottram studies the Greenland and Antarctic ice sheets and sea level rise for the Danish Meteorological Institute, but it's not the science that worries her.
"I'm less concerned that there are unknown processes going on that we don't understand, and there could potentially be some unforeseen catastrophe on the way," she said. "We know what a lot of the impacts are going to be. I think what keeps me awake at night in a metaphorical sense is really the interaction between the physical system and how human societies are going to handle it."
Giving the example of sea level, she says we will see a meter rise this century — in our lifetimes or that of our children — and will have to make tough decisions about our coastal cities. But she says it won't end there.
"I think that human societies have not really grasped what that means and that adaptation to sea level rise is going to be a long process and we are going to be doing it for hundreds of years," said Mottram, suggesting that we start thinking in terms of the lifetimes of cities (hundreds of years) rather than just human lifetimes.
Protecting the Vulnerable
Vladimir Romanovsky, a professor of geophysics at the University of Alaska Fairbanks' Permafrost Laboratory, said that while he thinks about how what happens in the Arctic will affect the rest of the world, his concerns are much more local.
"We should remember that there are still some people living in the Arctic," he said. Around 4 million people in fact who would have to deal with the real-life consequences of solid ground thawing beneath their feet and houses. "Changes in these local or regional kind of climates and environments, they impact these people and some of these impacts could be very severe."
Closer to the planet's other pole, Carolina Vera fears that existing inequalities will only be exacerbated by climate change.
"Climate change is already impacting the most vulnerable sectors of our planet," said Vera, who studies climate variability as a principal researcher for the National Council of Science of Argentina, a professor at the University of Buenos Aires and chief of staff for Argentina's Ministry of Science and Technology. Her work has led her to incorporate local knowledge and data collection into studies, involving communities that are balancing the problems of deforestation with their need to farm.
Heat and New Extremes
Perhaps not surprisingly, global heating is a key concern for many researchers, like Dim Coumou, who studies extreme weather at Vrije Universiteit Amsterdam.
Of most concern to him are heat and humidity extremes in the tropics – especially highly populated parts like West Africa, Pakistan and India – which will make it unbearable to be outside. When cooling down by sweating is no longer possible, people can't work outside and therefore can't grow food. The likely result being mass migration.
But it's not just the tropics.
Closely related to heat is the increase in extreme weather brought on by a warming climate. Coumou and his colleagues' research shows how changes to the jet stream will lead to more extreme weather in Europe, including floods and droughts.
This increase in extreme weather is climate scientist Abubakr Salih Babiker's biggest climate concern.
"A warmer atmosphere can hold more water in it and when it rains, it rains heavily leading to floods. A warmer ocean can lead to stronger tropical cyclones," said Babiker, who works for the East African Climate Center ICPAC in Nairobi. He explained that cyclones gain more energy from warmer water.
"We have seen evidence of all these events," he said. "The strongest tropical cyclones to impact the Arabian Peninsula, Somalia, and Mozambique occurred in the past 20 years!"
Science for Solutions
Pests, drought and flooding are on Esther Ngumbi's mind too.
An entomologist and professor of African American studies at the University of Illinois at Urbana-Champaign, she said that what keeps her up at night is the thought: "How can my science truly help?"
Ngumbi's work on pest and drought-resistant crops is driven by her concerns for vulnerable farmers who live in countries lacking social safety nets, where one season of crop devastation due to insects can mean going hungry and being unable to pay for their children's education.
"That truly makes me wake up every day and go to the lab to understand how my research can contribute to solutions that we need," she said.
Natasha Picone – an urban climatologist at the National University of Central Buenos Aires – says it's the solutions that occupy her thoughts too.
"With the pandemic, I realized that we are not doing enough for changing our cities to be more livable," she said. Her research informs urban planners about phenomena such as the urban heat island effect, air pollution and urban run-off that can lead to flooding. "If we don't change the path now, it will be really difficult to go back."
Weighing on the mind of oceanographer Renata Hanae Nagai at the University of Parana in Brazil is her four-year-old nephew and what his life will look like in a warmer world, but he also gives her hope. During a recent trip to the beach to watch nesting turtles, he warned others to leave the turtles alone.
She sees this same care in her students – learning about problems and coming up with solutions.
"People are the solution," she said. "We try, even under the hardest conditions."
'Scientists are Humans' Too
"For me, that's like morally totally unacceptable what they do – they lie," said the climate physicist from Maynooth University in Ireland, reflecting on encountering such people at public talks. "I mean, you can't argue with climate."
But this only pushes Caesar to better communicate what the science shows.
They Worry About Us
A common thread of this (rather unscientific) survey is that while we laypeople might be worrying about what the science says, climate scientists are often worrying about us.
"Scientists always think about what are the results of their studies, how are they important for, you know, for usual people, for normal people," the permafrost scientist told me. While doing his research, Romanovsky said he's always thinking about "how this could be used to make life of people easier or more predictable."
Reposted with permission from Deutsche Welle.
By Peter Giger
The speed and scale of the response to COVID-19 by governments, businesses and individuals seems to provide hope that we can react to the climate change crisis in a similarly decisive manner - but history tells us that humans do not react to slow-moving and distant threats.
Our evolution has selected the "fight or flight" instinct to deal with environmental change, so rather like the metaphor of the frog in boiling water, we tend to react too little and too late to gradual change.
Climate change is often described as global warming, with the implication of gradual changes caused by a steady increase in temperatures; from heatwaves to melting glaciers.
But we know from multidisciplinary scientific evidence - from geology, anthropology and archaeology - that climate change is not incremental. Even in pre-human times, it is episodic, when it isn't forced by a human-induced acceleration of greenhouse gas emissions and warming.
There are parts of our planet's carbon cycle, the ways that the earth and the biosphere store and release carbon, that could trigger suddenly in response to gradual warming. These are tipping points that once passed could fundamentally disrupt the planet and produce abrupt, non-linear change in the climate.
A Game of Jenga
Think of it as a game of Jenga and the planet's climate system as the tower. For generations, we have been slowly removing blocks. But at some point, we will remove a pivotal block, such as the collapse of one of the major global ocean circulation systems, for example the Atlantic Meridional Overturning Circulation (AMOC), that will cause all or part of the global climate system to fall into a planetary emergency.
But worse still, it could cause runaway damage: Where the tipping points form a domino-like cascade, where breaching one triggers breaches of others, creating an unstoppable shift to a radically and swiftly changing climate.
One of the most concerning tipping points is mass methane release. Methane can be found in deep freeze storage within permafrost and at the bottom of the deepest oceans in the form of methane hydrates. But rising sea and air temperatures are beginning to thaw these stores of methane.
This would release a powerful greenhouse gas into the atmosphere, 30-times more potent than carbon dioxide as a global warming agent. This would drastically increase temperatures and rush us towards the breach of other tipping points.
This could include the acceleration of ice thaw on all three of the globe's large, land-based ice sheets – Greenland, West Antarctica and the Wilkes Basin in East Antarctica. The potential collapse of the West Antarctic ice sheet is seen as a key tipping point, as its loss could eventually raise global sea levels by 3.3 meters with important regional variations.
More than that, we would be on the irreversible path to full land-ice melt, causing sea levels to rise by up to 30 meters, roughly at the rate of two meters per century, or maybe faster. Just look at the raised beaches around the world, at the last high stand of global sea level, at the end of the Pleistocene period around 120,0000 years ago, to see the evidence of such a warm world, which was just 2°C warmer than the present day.
Cutting Off Circulation
As well as devastating low-lying and coastal areas around the world, melting polar ice could set off another tipping point: a disablement to the AMOC.
This circulation system drives a northward flow of warm, salty water on the upper layers of the ocean from the tropics to the northeast Atlantic region, and a southward flow of cold water deep in the ocean.
The ocean conveyor belt has a major effect on the climate, seasonal cycles and temperature in western and northern Europe. It means the region is warmer than other areas of similar latitude.
But melting ice from the Greenland ice sheet could threaten the AMOC system. It would dilute the salty sea water in the north Atlantic, making the water lighter and less able or unable to sink. This would slow the engine that drives this ocean circulation.
Recent research suggests the AMOC has already weakened by around 15% since the middle of the 20th century. If this continues, it could have a major impact on the climate of the northern hemisphere, but particularly Europe. It may even lead to the cessation of arable farming in the UK, for instance.
It may also reduce rainfall over the Amazon basin, impact the monsoon systems in Asia and, by bringing warm waters into the Southern Ocean, further destabilize ice in Antarctica and accelerate global sea level rise.
The Atlantic Meridional Overturning Circulation has a major effect on the climate. Praetorius (2018)
Is it Time to Declare a Climate Emergency?
At what stage, and at what rise in global temperatures, will these tipping points be reached? No one is entirely sure. It may take centuries, millennia or it could be imminent.
But as COVID-19 taught us, we need to prepare for the expected. We were aware of the risk of a pandemic. We also knew that we were not sufficiently prepared. But we didn't act in a meaningful manner. Thankfully, we have been able to fast-track the production of vaccines to combat COVID-19. But there is no vaccine for climate change once we have passed these tipping points.
We need to act now on our climate. Act like these tipping points are imminent. And stop thinking of climate change as a slow-moving, long-term threat that enables us to kick the problem down the road and let future generations deal with it. We must take immediate action to reduce global warming and fulfill our commitments to the Paris Agreement, and build resilience with these tipping points in mind.
We need to plan now to mitigate greenhouse gas emissions, but we also need to plan for the impacts, such as the ability to feed everyone on the planet, develop plans to manage flood risk, as well as manage the social and geopolitical impacts of human migrations that will be a consequence of fight or flight decisions.
Breaching these tipping points would be cataclysmic and potentially far more devastating than COVID-19. Some may not enjoy hearing these messages, or consider them to be in the realm of science fiction. But if it injects a sense of urgency to make us respond to climate change like we have done to the pandemic, then we must talk more about what has happened before and will happen again.
Otherwise we will continue playing Jenga with our planet. And ultimately, there will only be one loser – us.
Reposted with permission from World Economic Forum.
The Earth has lost 28 trillion tonnes (approximately 31 trillion U.S. tons) of ice in just 23 years, and the climate crisis is largely to blame.
The finding comes in a review paper published in The Cryosphere this month that used satellite data and numerical modelling to calculate all the ice that melted worldwide between 1994 and 2017.
"In the past researchers have studied individual areas – such as the Antarctic or Greenland – where ice is melting. But this is the first time anyone has looked at all the ice that is disappearing from the entire planet," study coauthor and director of Leeds University's Centre for Polar Observation and Modelling Andy Shepherd told The Guardian. "What we have found has stunned us."
Over 28,000,000,000,000 tonnes of ice has melted in last 30 years - enough to cover the entire surface of the UK in… https://t.co/ohZ6IIVFcl— Prof. Dan Parsons 🇪🇺 🌏💧🛰🌊⚽️🏏⛳🏈 (@Prof. Dan Parsons 🇪🇺 🌏💧🛰🌊⚽️🏏⛳🏈)1598173688.0
Arctic sea ice, Antarctic ice shelves, mountain glaciers, the Greenland and Antarctic ice sheets, and Southern Ocean sea ice all lost mass during the study period, the researchers wrote. About 68 percent of those losses were caused by warmer air temperatures, while the remaining 32 percent were caused by warmer ocean water.
"There can be little doubt that the vast majority of Earth's ice loss is a direct consequence of climate warming," the researchers wrote, as The Guardian reported.
In fact, the total ice loss recorded matches the worst-case scenario predicted by the Intergovernmental Panel on Climate Change (IPCC). And it's likely to get worse. The researchers prognosticate a meter (approximately three feet) of sea level rise by 2100.
"To put that in context, every centimetre of sea level rise means about a million people will be displaced from their low-lying homelands," Shepherd told The Guardian.
But sea level rise isn't the only consequence of ice melt. For one thing, the melting ice exposes darker ocean waters or soil, which absorb the sun's heat rather than reflect it, increasing global heating. The fresh water melting from ice sheets also disrupts Arctic and Antarctic ocean ecosystems, while the loss of mountain glaciers threatens the drinking water of several communities.
"What more can be said? What further evidence are we waiting for?" UK Green Party co-leader Caroline Lucas tweeted in response to the news. "Feel so overwhelmingly sad - and so angry too. We can't say we didn't know. Are we really saying we just didn't care?"
What more can be said? What further evidence are we waiting for? Feel so overwhelmingly sad - and so angry too W… https://t.co/cvYV9ore53— Caroline Lucas (@Caroline Lucas)1598176086.0
This has been a bad summer for ice news. Another study published this month found that Greenland's ice sheet had reached the "point of no return" and would continue to melt even if the climate crisis were halted. A third study found that Greenland lost a record amount of ice in 2019.
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