Will 2023 be the hottest summer in the past 2,000 years? | Environmental News

Hottest summer in the past 2,000 years

Last year's summer was so hot that it left a deep impression on everyone. A new study published in Nature pointed out that 2023 was the hottest summer in the past 2,000 years.

Directly measured temperature records can only be traced back to more than 100 years ago, and the records are limited to Europe and other regions. Climate analysis of ice sheets and sediments can be traced back to tens of thousands of years ago, but the resolution is about 300 years, and it is impossible to be specific to annual temperature changes. Is there any way to trace back thousands of years and be able to be detailed to annual temperature changes? Researchers have set their sights on trees.

Trees can provide indirect temperature data from thousands of years ago . Trees growing in temperate climates produce obvious annual rings every year. In spring and summer, the temperature is high and the water is sufficient, so the trees grow rapidly and the wood is loose. In autumn and winter, as the temperature drops, the growth of trees slows down and the wood is dense. This cyclical change forms annual rings on the cross section of the tree trunk .

Trees grow faster in spring and summer, and slower in autumn and winter | NASA

However, the researchers were unable to find tree ring records in the southern hemisphere, and the tree rings formed by tropical trees are different from those in temperate zones because of the lack of obvious temperature changes. Therefore, the researchers limited the area for tree ring analysis to the area between 30 degrees and 90 degrees north latitude.

Based on these records, the researchers found that the summer of 2023 was clearly the warmest in the past 2,000 years . The summer of 2023 was 0.15 degrees Celsius warmer than the record-breaking summer of 2016. Last summer was at least 0.5 degrees Celsius warmer than the summer of 246 AD - the hottest summer before human activities affected the global climate by burning fossil fuels . The summer of 2023 was 3.96 degrees Celsius warmer than the summer of 536 AD - the coldest summer in the tree ring record, when volcanic eruptions caused particles floating in the atmosphere to reflect sunlight.

References[1]

Researcher Jan Esper believes that the record-breaking summer heat in 2023 was man-made, and he hopes that these findings will make people realize the urgency of reducing greenhouse gas emissions and abandoning fossil fuels.

Construction of the largest vacuum cleaner begins in Iceland

On May 8, Mammoth, a device that extracts carbon dioxide from the air, started construction in Iceland. This is the second direct air carbon capture (DAC) device started up by Climeworks in Iceland. It is the largest of its kind in the world and is ten times larger than its predecessor, Orca.

The super-large "vacuum cleaner" sucks carbon dioxide｜Climeworks

To achieve the goal of limiting global warming to 2°C (preferably 1.5°C), it is necessary not only to reduce greenhouse gas emissions, but also to take additional measures to reduce the concentration of carbon dioxide in the atmosphere - scientists estimate that billions of tons of carbon must be removed from the atmosphere every year . Direct air carbon capture is one of these measures, which captures carbon dioxide directly from the air and then stores it or uses it for other purposes .

Mammoth is designed to capture 36,000 million tons of CO2 per year. The captured CO2 will be transported underground and converted into stone through natural reactions with basalt , which will be stored permanently underground.

Climeworks

Direct air carbon capture technology consumes a lot of energy. Thanks to Iceland's natural geographical advantages, Climeworks' factory in Iceland uses local renewable low-temperature power plants to generate electricity .

Critics of direct air carbon capture say it's too expensive and that sucking carbon dioxide out of the air distracts companies from thinking about how to reduce carbon emissions as much as possible. Climeworks didn't say how much it would cost Mammoth to remove each ton of carbon dioxide, but said it would work to get that down to $400 to $600 a ton by 2030 and $200 to $350 a ton by 2040.

Could the air in your car be contaminated with carcinogens?

In order to improve the fire resistance of materials, flame retardants may be added to our electronic devices, blankets, and seats. However, some flame retardants have the risk of causing cancer.

Recently, a study published in Environmental Science and Technology stated that the air inside private cars may be contaminated by flame retardants, many of which are either known carcinogens or suspected carcinogens . Considering that some people have long commutes, staying in a car for a long time may be harmful to health.

Flame retardants are often added to seats | Tuchong Creative

Researchers tested the air inside 101 cars in the U.S. (including electric, gasoline and hybrid vehicles) and found that 99% of them contained a flame retardant called TCIPP. This flame retardant has been found to increase the risk of cancer in rats and is under investigation by the U.S. National Toxicology Program. Many cars were also found to contain two flame retardants, TDCIPP and TCEP, both of which are carcinogens pointed out by California Proposition 65.

Rising temperatures in summer will also lead to higher concentrations of flame retardants in the car, so try to park your car in the shade or open the windows in summer . The researchers also emphasized that the hazards of flame retardants should be determined and the standards for adding flame retardants should be adjusted to reduce health risks.

Inhalation of plastic particles

In addition to eating plastic directly, inhaling plastic particles is also a major way for us to passively ingest plastic . A new study from the University of Technology Sydney simulated what happens when humans inhale different types of plastic particles and where they end up in the human body.

Researchers say plastic air pollution is very common . Cosmetics and personal care products used in daily life, such as toothpaste, will deliberately add microplastic particles to exfoliate or increase the viscosity of the product. Some plastic products, such as plastic water bottles and clothing, will also release tiny plastic particles.

The study found that synthetic textiles are the main source of plastic particles in indoor air , while there are multiple sources in the outdoor environment, including aerosols from the ocean and plastic particles from wastewater treatment.

Marine plastic waste breaks down into tiny plastic particles, which combine with other substances such as salt to form polluted aerosols, which are eventually deposited on land by the wind; microplastic particles are difficult to completely filter out during wastewater treatment, and are discharged into the environment with treated water or sludge. | Shawn Heinrichs

The study found that breathing rate, plastic particle size and shape determine where plastic particles are deposited in the respiratory system. Faster breathing rates lead to increased plastic particle deposition in the upper respiratory tract (especially larger microplastic particles). Slower breathing allows smaller plastic particles, such as nanoplastic particles, to penetrate and deposit more deeply. Compared with spherical microplastic particles and nanoplastics, non-spherical microplastic particles penetrate deeper into the lungs.

Researcher Suvash Saha said plastic particles amplify human susceptibility to a range of lung diseases, including chronic obstructive pulmonary disease, fibrosis, dyspnea, asthma and the formation of ground glass nodules.

Robots hunt down microplastics and bacteria

Microplastics are smaller than 5mm and are difficult to clean. They also absorb bacteria that can cause disease, posing a greater threat to human health.

In order to remove microplastics and bacteria from water at the same time, a research team from the Brno University of Technology in the Czech Republic has developed a micro-machine system that consists of many small parts working together to mimic biological groups in nature, such as schools of fish.

The research team experimented with Pseudomonas aeruginosa, which can cause pneumonia, and found that the microrobots successfully captured about 80% of the bacteria and were also able to capture free plastic particles . After capturing bacteria and microplastics, the researchers collected the robots and used ultrasound to separate the bacteria, then exposed the robots to ultraviolet light for disinfection so that they could be reused .

The robot (light yellow) collects bacteria (green) and microplastics (grey).

Author: Yellow pollock

Editor: Mai Mai