factor

Microplastics and antibiotic resistance

April 14, 2025 By EarthWise Leave a Comment

Microplastics are a real problem. They are pretty much everywhere. They are in our food, in the oceans, on mountains, up in the clouds, and most alarmingly, in our bodies. All of that is already bad news, but researchers at Boston University have found that microplastics may also be contributing to antibiotic resistance in dangerous bacteria.

The researchers observed that bacteria exposed to microplastics become resistant to multiple types of antibiotics commonly used to treat infections. Bacteria can become resistant to antibiotics for a number of reasons, including misuse and overprescribing of medications. However, a major factor influencing antibiotic resistance is the microenvironment – the immediate surroundings of a microbe – which is where bacteria and viruses replicate.

The Boston University study tested how the common bacterium E. coli reacted to being in a closed environment with microplastics. The plastics provide a surface that the bacteria can attach to and colonize. When attached to a surface, bacteria create a sticky substance called a biofilm that acts like a shield, protecting the bacteria and keeping them affixed securely. The tests showed that microplastics supercharged the biofilms so much that when antibiotics were introduced, they were unable to penetrate the shield.

Microplastics are everywhere, but they are especially prevalent in impoverished places where sanitation may be limited. Refugees, asylum seekers, and forcibly displaced populations are already at increased risk of contracting drug-resistant infections. The prevalence of microplastics adds another risk to the already difficult lives of these people.

**********

Web Links

Microplastics Could Be Fueling Antibiotic Resistance, BU Study Finds

Photo, posted May 15, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A structural battery

October 25, 2024 By EarthWise Leave a Comment

The size and especially the weight of batteries is a critical factor for most things that use them. Battery weight is a key limitation for computers and cell phones. It is even more of a limitation for electric cars, ships, or planes.

If the battery of a device or vehicle can also function as a load-bearing structure, its weight and energy consumption can be dramatically reduced. This concept of a structural battery is sometimes called massless energy storage. It has the potential to halve the weight of a laptop computer, make cell phones as thin as a credit card, and increase the range of an electric car by as much as 70%.

Researchers at Chalmers University in Sweden have been working on structural battery technology for many years. Their first published results in 2018 showed how stiff, strong carbon fibers could be used for chemical storage of electrical energy.

Since then, they have been creating batteries with increasing energy density. Their latest versions still have only a quarter of the capacity of today’s lithium-ion batteries. But if batteries can be part of the structure of a vehicle, for example, and can be made of lightweight materials like carbon fiber, then the overall weight of the vehicle can be greatly reduced and not nearly as much energy will be needed to power it.

The goal of the Chalmers research is to achieve battery performance that makes it possible to commercialize the technology. There is a lot of engineering work to be done before these structural batteries can go from laboratory proofs of concept to real world use. But the potential is quite promising.

**********

Web Links

World’s strongest battery paves way for light, energy-efficient vehicles

Photo, posted August 8, 2024, courtesy of NOI Techpark via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How warm is It?

August 8, 2024 By EarthWise Leave a Comment

As of June, the world had seen 13 consecutive months of record-breaking heat. The average global temperature over the last 12 of those months measured 1.5 degrees Celsius warmer than the preindustrial era. This means that the world has at least temporarily exceeded the temperature target set forth in the Paris Climate Agreement.

Does this mean that climate change has gotten to the point where keeping temperatures below that goal is no longer possible? Not necessarily. Temperatures could drop below the 1.5-degree level in the near future.

The world has certainly been warming as a result of climate change, but the spike in temperature for the past year has also been driven by an El Niño condition in the Pacific, which leads to warmer temperatures. How much of the warming is a result of each factor is not known.

But scientists say that El Niño has ended in June and a La Niña condition is likely to take shape between August and October. This would lead to cooler temperatures in many places.

Despite the extensive and lingering heatwaves in the US in July, on a global scale, temperatures have actually started falling in July. July may end up being the first month since June 2023 to not set a new monthly global temperature record. Nevertheless, the long streak of record-high temperatures is no statistical anomaly. It is indicative of a large and continuing shift in the climate. Whether conditions in the Pacific produce an El Niño or a La Niña, the steady long-term warming will continue as long as human-generated carbon emissions continue.

**********

Web Links

How Bad Is Warming? La Niña May Reveal

Photo, posted September 19, 2022, courtesy of Paul Sableman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Species and climate change

July 4, 2024 By EarthWise Leave a Comment

Temperature extremes on Earth currently range from a low of -129°F to a high of 134°F. But these climatic limits have changed throughout history. In fact, during the last interglacial period 130,000 years ago, temperatures were warmer, resembling what we are projected to experience at the end of this century.

Species that evolved during such periods may possess pre-adaptations that could help them tolerate upcoming changes to the climate. This factor is often overlooked by traditional statistical models predicting species’ responses to climate change.

But a new model, developed by researchers from Ifremer in France and Lausanne University in Switzerland, has taken this oversight into account, and reassessed the proportion of terrestrial and marine species threatened with extinction by climate change.

In the study, which was recently published in the journal Nature Ecology and Evolution, the research team applied its model to nearly 25,000 terrestrial and marine species from around the world. The researchers discovered that 49% of these species live in climate niches near the current climatic limits, and 86% could potentially extend beyond these limits.

The most surprising result concerns tropical regions. While forecasts from traditional models estimate that the diversity of terrestrial species in tropical areas could decrease by 54% between now and 2041-2060, the new model predicts a more moderate decline of 39%.

The findings confirm the importance of taking urgent measures to mitigate climate change and its impact on biodiversity.

**********

Web Links

Some species may better tolerate climate change than expected

Photo, posted October 23, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Global Stilling | Earth Wise

October 20, 2022 By EarthWise Leave a Comment

During the summer of 2021, much of Europe experienced a “wind drought” – wind speeds in many places were about 15% below average. In the UK in particular, winds were unusually calm and wind energy production was dramatically reduced.

Globally, wind speeds have been dropping by about 2.3% per decade since the 1970s. In 2019, however, global average windspeeds actually increased by about 6%. The question is whether a trend of slowing winds – so-called global stilling – is associated with climate change or is just natural variability in action.

Wind results from uneven temperatures in air masses. Much of the world’s wind comes from the difference between the cold air at the poles and the warm air at the tropics. Because the Arctic is warming much faster than the tropics, it is possible that winds will continue to decline around the world.

Another factor people cite is the increase in surface roughness. The number and size of urban buildings continues to increase, which acts as a drag on winds.

Some models predict that wind speeds will decrease over much of the western U.S. and East Coast, but the central U.S. will see an increase. Experts do not all agree about what is happening with global winds. Many believe that the observed changes to date have been within the range of variability. Furthermore, some places have been windier than usual.

All of this really matters for many reasons. Europe is increasingly dependent upon wind power as an alternative to fossil fuels. A 10% drop in wind speed results in a 30% drop in energy generation. Whatever their cause may be, wind droughts cannot be ignored.

**********

Web Links

Global ‘Stilling’: Is Climate Change Slowing Down the Wind?

Photo, posted June 28, 2008, courtesy of Patrick Finnegan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air Pollution Reduction And Global Warming | Earth Wise

April 13, 2021 By EarthWise Leave a Comment

The world is dealing with two serious problems affecting the atmosphere: the growing levels of carbon dioxide leading to a warming climate and the effects of air pollution on human health. It turns out that these two things are connected in complicated ways.

Countries around the world are racing to mitigate global warming by limiting carbon dioxide emissions. The combustion of fossil fuels as well as wood and other biomass produces sulfate aerosols, which are associated with acid rain as well as many human health problems. Air pollution causes an estimated seven million premature deaths per year worldwide, so reducing it is imperative.

The complication is that sulfate aerosols in the upper atmosphere actually have a cooling effect on surface air temperatures. Aerosols create bigger clouds and increase light scattering, both of which result in less sunlight reaching the surface. Large natural sources of sulfate aerosols – such as volcanic eruptions – can temporarily cool the earth until they settle out of the atmosphere.

There are many kinds and sizes of atmospheric aerosols, making predicting their effects and behavior difficult. For example, black carbon aerosols from forest fires tend to suppress cloud formation by warming the air and making tiny water droplets evaporate. However, sulfate aerosols from burning fossil fuels make clouds grow larger.

Analysis has shown that air pollution has actually reduced the amount of warming that has taken place to date. A new study by Kyushu University in Japan looked at the long-term climate effects of reductions in sulfate aerosols. The loss of cooling effect from light-scattering aerosols as emissions are reduced is a factor that cannot be ignored.

**********

Web Links

Air pollutant reductions could enhance global warming without greenhouse gas cuts

Photo, posted January 23, 2021, courtesy of Wutthichai Charoenburi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.