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Are Banks Banking on Climate Chaos?

May 19, 2024

Banks May Lose Money If the World Combats Climate Change

At least one major U.S. bank stands to lose billions of dollars if the world takes immediate steps to curb greenhouse gas emissions to achieve net zero by 2050. A confidential analysis prepared by Citigroup and obtained by Reuters, concluded that the bank would suffer losses of more than $10 billion over ten years if immediate steps were taken to combat climate change. 

The Citigroup financial institution said in a report that it would lose billions of dollars if efforts to combat climate change were sped up.  |  Credit: yuankuei/Flickr

The bank would still lose money, even if measures to fight climate change stayed as they are now, but $3 billion less than under policies to reach the net zero scenario in 25 years, which is the goal called for in the Paris Agreement.

Banks, including Citigroup, have pledged to cut their own emissions to net zero by 2050, but will struggle to manage their financial exposure, according to one banking expert who spoke with Reuters. Citigroup is the fourth largest bank in the U.S. in terms of assets.

According to the news agency, the Citigroup analysis said that the losses would occur from borrowers in the oil, gas, and real estate sectors, which will suffer financially. The report was prepared by Citigroup in response to the Federal Reserve’s directive to six major U.S. banks to disclose how they plan to manage climate change impacts. The Fed released its own report based on the six institutions’ responses.

Banks are continuing to finance fossil fuels even though the International Energy Agency’s position is that if we are to achieve net zero by 2050, no new fossil fuels can be developed. Forbes reports that about $350 billion was loaned to fossil fuel companies in 2023 for expansion alone, which leads to their conclusion that the banks are “banking on climate chaos.”

A Dispute Is Growing Between the U.S. and Mexico Over Water

A major dispute between the U.S. and Mexico is brewing, and it does not involve drugs or immigration. Rather, it involve water. Bipartisan members of Congress from Texas are demanding that funds be withheld from Mexico because of its failure to deliver the water it owes to the U.S. in two reservoirs on the Rio Grande River.

Amistad Reservoir is a man-made lake along the Texas-Mexico border that stores water from the U.S. and Mexico. Texas congress members say Mexico is behind in making its water contributions—to the detriment of farmers and municipalities.  |  Credit: Alex Demas/USGS

A treaty signed by the two countries in 1944 obligates Mexico to deliver 1.75 million acre-feet of water every five years into reservoirs shared by the two countries, about the equivalent used by one million households on an average annual basis. While Mexico has until next year to honor its commitment, it has fallen behind in making regular deliveries, according to the International Boundary Commission.

The result is that one of the reservoirs, which straddles the border, holds less than 30 percent of the U.S. share of water, and the other reservoir holds only 12 percent. The shortage is having effects. Some communities in Texas are having to stretch their limited supplies as long as possible, and a sugar processing plant that employed over 500 workers had to shut down. Farmers in the region are suffering from the lack of water, according to the Texas Tribune.

The Washington Post reports that in the last 80 years, Mexico has damned its rivers and built new reservoirs. Luis Ribera, a professor at Texas A&M University, told the Post that since the signing of the North American Free Trade Agreement, agriculture in Mexico has shifted toward water-demanding fruits and vegetables to be sold in U.S. markets

In its defense, Mexico’s position is that drought has made it difficult to deliver the water, and it has not yet violated the treaty. According to Texas Public Radio, the issue of how Mexico could evade making its water contributions is a hot topic in the presidential election on June 2.  

The same treaty obligates the U.S. to deliver almost as much Colorado River water to Mexico annually.

Glass Made from Bamboo Is Flame-Retardant and Water-Repellent

Many of the world’s windows are made with silica glass derived from sand. They are transparent and strong, but manufacturing them has a high carbon footprint and leaves behind a waste product that’s not biodegradable.

Credit: Shannon Tompkins/Flickr

Recently, scientists have been developing glass made from transparent wood as an environmentally better option. while those solutions are strong, have a lower carbon footprint, and offer good thermal insulation, trees take a long time to replenish, and the polymers used in making the windows pose a significant fire risk.

What to do? Enter bamboo. While technically a grass, bamboo has a lot in common with wood—mainly that it consists of lignin and cellulose—but has none of the downsides when it comes to making glass. Researchers at the College of Materials Science and Engineering at CSUFT in China have created a transparent bamboo material that allows in natural light but is also flame-retardant, water-repellent, and able to block smoke and carbon monoxide.

Bamboo grows fast and can be used as a building material within four to seven years. It also has an output four times higher per acre than wood. The team adds that beyond windows, the bamboo material could be used as a substrate for perovskite solar cells to make them more efficient.

The study was published in the journal Research.

How to Safely Kill Pests on Crops? Stick It to Them

Carnivorous plants—plants that eat insects—are fascinating and perhaps creepy if you saw the musical Little Shop of Horrors, where one (Audrey II) feeds on human flesh and blood. Rest assured that plants entrap only small bugs, whether by ensnaring them in their leaves or by secreting a type of glue to catch and disable their prey. It’s that last sticky tactic that gave researchers in The Netherlands an idea.

Carnivorous plants, such as sundews, trap their prey with sticky hairs.  |  Credit: Alan Rockefeller/Creative Commons

Teams from Wageningen and Leiden Universities wanted to see if they could mimic the “insect glue” that plants called sundews generate to trap bugs and use it to protect crops. They transformed vegetable rice oil into a yellow, sticky substance by blowing air over it and then grinding it into small particles, which resulted in beads that were as sticky as duct tape. They then sprayed the drops on chrysanthemum leaves, to see if it could trap a small insect called Californian thrips (Frankliniella occidentalis) that causes major problems in greenhouses worldwide.

In their study, more than 60 percent of the thrips were captured within the two days, and the drops remained sticky on the leaves for weeks—even if they got wet. The team says their adhesive could be a sustainable replacement for toxic chemical pesticides that affect human health, biodiversity, and the environment. They add that unlike common pesticides, insects are unlikely to develop resistance to the glue as they would have to evolve over time to become bigger and stronger. Furthermore, the adhesive droplets were small enough to capture only the target pest and not trap beneficial insects like pollinators.
The team is next exploring adding attractive scents to lure in prey and plan to investigate using agricultural waste oils to make the solution even more sustainable.

The study was published in the journal Proceedings of the National Academy of Sciences (PNAS).