Highlights from the Week's News

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Where’s Crawford Lake—and Why Should You Care?

July 16, 2023

Canada Calls for Moratorium on Seabed Mining

Last week, the International Seabed Authority (ISA) began a ten-day meeting in Kingston, Jamaica, to negotiate draft regulations about the exploitation of mineral resources from the bottom of the ocean by mining companies. The outcome could determine whether a Canadian enterprise known as The Metals Company will be allowed to apply for a permit to mine the seabed for mineral-rich nodules containing copper, manganese, nickel, lithium, and more, which could be used in smartphones, wind turbines, solar panels, and batteries.

There’s widespread concern that using heavy machinery to extract the metal-rich rocks could irreparably harm marine ecosystems by churning up sediment and destroying habitat. Critics say that there is little understanding of the risks from the extractive process.

As the meeting of the ISA got underway, the Canadian government announced that it supports a moratorium on commercial seabed mining. Canada joins various countries including Sweden, Ireland, Germany, France, and New Zealand, as well as manufacturers such as BMW, Volvo, and Samsung in calling for a halt. However, some countries, including China, Japan, Norway, and South Korea want permitting regulations to go forward.

A new study was published last week warning that some fish species, including tuna, are changing their migration patterns because of climate change and are starting to move into areas of the Pacific Ocean between Hawai’i and Mexico where companies want to mine. Now, seafood groups too are asking for a pause on deep-sea mining that could disrupt ecosystems, which took millions of years to form, according to Catherine Coumans, of MiningWatch Canada, who spoke to the CBC.

The ISA meeting is scheduled to continue through July 21.

Mud at the Bottom of This Lake Shows the Beginning of the "Anthropocene"

A small lake not far from Toronto, Canada, best shows how Earth’s environment began a new epoch brought on by humans called the “Anthropocene.” Scientists chose Crawford Lake because sediment deep at its bottom contains fallout from intense fossil fuel burning and plutonium bomb tests. They say mud at the bottom of the lake reflects the 70-year period in which human activity caused more changes to the environment than occurred in the previous 7,000 years—referred to as the Great Acceleration.

Crawford Lake, Ontario, Canada | Credit: Whpq/Creative Commons

The researchers, known as the Anthropocene Working Group, plan to determine a specific date that the new human-generated epoch started by analyzing the plutonium levels at the bottom of the lake. According to one of the researchers, Andy Cundy, a professor at the University of Southampton who spoke to AFP, the data already show a clear shift around the mid-20th century from the earlier Holocene epoch that began about 11,700 years ago as the last ice age ended.

Crawford Lake was selected from among 11 other possible sites around the world. According to one scientist, it has a remarkably preserved record of annual deposits. Core samples from the lake show layers that resemble tree rings, and those from the 1950s on, indicate fertilizers and microplastics in addition to plutonium.

How humans have changed the Earth was vividly demonstrated over the past week with unprecedented conditions, including extreme heat in Europe, China, and the U.S., as well as flooding from heavy rainfall in Japan, India, and the U.S.  Hundreds of Canadian wildfires have been burning for months. Sea surface temperatures have reached new highs, and Antarctic ice was nearly 20 percent below the previous record for June. In addition, a study published last month showed that pumping groundwater has led to the North Pole shifting.

The beginning of a cyclical El Niño weather pattern contributes to some of these events, but they might not have been so destructive had there been no, or less global warming. According to the Washington Post, scientists have shown that the links between climate change and weather disasters are abundantly clear. 

Climate Change Is Turning the Ocean Green

As recent days will attest, climate change is affecting our planet in numerous ways—droughts, floods, heat waves, extreme storms—and now, according to new research, it’s changing the color of the ocean. Waters in the sea appear a certain color depending on what’s in the upper layers. Generally, the ocean will look deep blue reflecting little life, whereas a greener tinge indicates microscopic organisms like phytoplankton which contain the green pigment chlorophyll that helps them harvest sunlight.

To track the changes in ocean color, scientists analyzed measurements of ocean color taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite, which has been monitoring ocean color for 21 years. | Credit: NASA and Joshua Stevens, using Landsat data from the U.S. Geological Survey and MODIS data from LANCE/EOSDIS Rapid Response

In a new study, researchers from MIT and the National Oceanography Centre (NOC) in the UK used data from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA's Aqua satellite to find that, in the last 20 years, 56 percent of the world’s oceans are getting greener—especially in tropical regions. They say the impact of climate change on plankton ecosystems is likely to blame.

Plankton are tiny organisms carried by tides and currents and are often divided into phytoplankton, which are small plants, and zooplankton, which are small animals. Phytoplankton are the foundation of ocean ecosystems and any imbalances could send ripples through the entire marine food web.  

Phytoplankton also play a huge role in the ocean’s ability to capture and store carbon dioxide. According to the latest data from the Intergovernmental Panel on Climate Change (IPCC), plankton could account for between five and 17 percent of new carbon intake into the ocean by 2100. At this point, the researchers can’t determine the exact changes going on in marine ecosystems but believe that global warming will lead to a dominance by smaller types of plankton, which could mean the ocean would store less carbon.

The study was published in the journal Nature.

“Molecular Scissors” Can Make Paper That's Better for the Environment

Paper products have a lot of green cred for being recyclable and biodegradable because they’re made from cellulose—the carbohydrates found in the cell walls of trees. But the paper and pulp industry is notorious for its environmental footprint for the amount of energy and water involved, plus the amount of toxic pollutants released—in part to separate cellulose from the woody part of a tree, its lignin.

CRISPR-modified poplar trees (l) and wild poplar trees grow in an NC State greenhouse. | Credit: Chenmin Yang, NC State University

So, what if you could make a tree with less lignin? That was the idea researchers at North Carolina State University had when they used the gene-editing system called CRISPR to breed poplar trees, often used in the paper industry, they say are more sustainable. You’ve probably heard of CRISPR, which is described as a kind of molecular scissors where researchers can add, remove, or change regions of an organism’s DNA. It’s being used in medicine and agriculture where it’s helped to treat cancer or produce disease-resistant rice.

After identifying three important genes associated with a poplar tree’s lignin production, the researchers were able to modify specific DNA segments to reduce lignin levels by 35 percent when compared to wild trees. They say the low-lignin trees could have numerous benefits, such as slashing greenhouse gases associated with pulp production by up to one-fifth if the technique is adopted on an industrial scale and reducing so-called black liquor, a toxic byproduct of the industry.

The next step would be to grow the CRISPR poplars outside to see if they’re strong enough to withstand natural conditions like wind. Also, the trees would have to get the approval of regulators, which might be easier than other engineered plants since they trees did not take DNA from other species like some crops do—they only had their genes edited to produce what the researchers hope will be a more popular poplar.

The findings were published in the journal Science.