• Skip to main content
  • Skip to primary sidebar

Earth Wise

A look at our changing environment.

Hide Search
You are here: Home / Archives for engineering

engineering

Should We Block The Sun? | Earth Wise

May 10, 2021 By EarthWise Leave a Comment

The risks of geoengineering need to be better understood

There is growing concern that greenhouse gas emissions are not falling quickly enough to avoid dangerous levels of global warming.  As a result, there is the impetus to examine other options.  Among these are geoengineering, which is one of the most contentious issues in climate policy.  Geoengineering embodies many risks that make even seriously considering it seem risky in itself.

Despite this, the National Academies of Science, Engineering, and Medicine has issued a report saying that governments urgently need to know whether solar geoengineering could work and what its side effects might be.

Solar geoengineering is also called solar radiation modification, which entails reflecting more of the sun’s energy back into space.  This would likely be accomplished by injecting aerosols into the atmosphere, much like what happens after large volcanic eruptions.

Schemes for solar geoengineering raise numerous issues.  Although solar geoengineering might cool the earth’s surface to a global temperature target, the cooling may not be evenly distributed, affecting many ecosystem functions and biodiversity.   It would likely upset regional weather patterns in potentially devastating ways, for example by changing the behavior of the monsoon in South Asia.  It might dangerously relax public commitments to reduce greenhouse emissions. 

Despite these concerns, or perhaps because of them, the committee that produced the report believes that technology to reflect sunlight deserves substantial funding and should be researched as rapidly and effectively as possible.  Once any geoengineering projects get into the hands of policymakers, they may gather momentum that bypasses the advice of scientists.  So, it important to make progress on the science while geoengineering is still only theoretical.

**********

Web Links

Should We Block the Sun? Scientists Say the Time Has Come to Study It.

To intervene or not to intervene? That is the future climate question

Photo, posted August 3, 2018, courtesy of Tomasz Baranowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Superstrong Nanofibers | Earth Wise

March 5, 2021 By EarthWise Leave a Comment

MIT research team has developed superstrong nanofibers

Self-assembly is a ubiquitous process in the natural world that leads to the formation of the DNA double helix, the creation of cell membranes, and to many other structures.   Scientists and engineers have been working to design new molecules that assemble themselves in water for the purpose of making nanostructures for biomedical applications such as drug delivery or tissue engineering.  For the most part, the materials created in this way have been chemically unstable and tended to degrade rapidly, especially when the water is removed.

A team at MIT recently published a paper describing a new class of small molecules they have designed that spontaneously assemble into nanoribbons with unprecedented strength and that retain their structure outside of water.

The material is modeled after a cell membrane.  Its outer part is hydrophilic (it likes to be in water) and its inner part is hydrophobic (it tries to avoid water.)  This configuration drives the self-assembly to create a specific nanostructure and by choosing the appropriate chemicals to form the structures, the result was nanoribbons in the form of long threads that could be dried and handled.  The resultant material in many ways resembles Kevlar.   In particular, the threads could hold 200 times their own weight and have extraordinarily high surface areas.  The fibers are stronger than steel and the high surface-to-mass ratio offers promise for miniaturizing technologies for such applications as pulling heavy-metal contaminants out of water and for use in electronic devices and batteries.

The goal of the research is to tune the internal state of matter to create exceptionally strong molecular nanostructures.  The potential for important new applications is considerable and exciting.

**********

Web Links

Researchers construct molecular nanofibers that are stronger than steel

Photo, posted June 19, 2007, courtesy of Andrew Hitchcock via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Toughest Beetle Of Them All | Earth Wise

December 3, 2020 By EarthWise Leave a Comment

Studying the toughest beetle of them all

In 2015, UC Riverside materials scientists placed a mottled black beetle in a parking lot and ran it over with a Toyota Camry.  Twice.  Crushed beneath the wheels of a 3,500-pound sedan, the inch-long insect made it through without a scratch.

For the past five years, a group of scientists have been studying this remarkable bug, which has the splendid name of the diabolical ironclad beetle. Using a combination of advanced microscopy, mechanical testing, and computer simulations, the researchers have figured out the secret of this beetle’s crush resistance.

The beetle’s super-toughness lies in two armorlike structures called elytra that meet in a line, called a suture, running the length of the abdomen.  The suture acts like a jigsaw puzzle.  It connects various exoskeletal blades – the puzzle pieces – in the abdomen under the elytra.   These structural components can act in different ways.  The interconnecting blades lock to prevent themselves from pulling out of the suture.  The suture and blades delaminate, leading to a graceful deformation rather than catastrophic failure.  These strategies dissipate energy to circumvent fracturing.

The researchers found that the diabolical ironclad beetle – just had to say that name again – can take on an applied force of about 150 newtons, a load at least 39,000 times its body weight.  (That’s the equivalent of a 150-pound person resisting the crush of about 25 blue whales).

An ongoing challenge for structural engineering is how to join together different materials without limiting their ability to support loads.  The strategies evolved in these beetles may be applicable in gas turbines of aircraft, for example, where metals and composite materials are joined together with mechanical fasteners.   We can learn things from the toughest beetle of them all.

**********

Web Links

Diabolical ironclad beetles inspire tougher joints for engineering applications

Photo, posted April 9, 2017, courtesy of Vahe Martirosyan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Engineering Mosquitoes | Earth Wise

February 21, 2020 By EarthWise Leave a Comment

Engineering mosquitoes to repel disease

Tropical regions grapple with the spread of diseases – such as dengue, yellow fever, zika, chikungunya, and malaria – by mosquitoes.  A fairly successful strategy has been the Sterile Insect Technique, which is essentially insect birth control. The process involves rearing large quantities of sterilized male mosquitoes in dedicated facilities, and then releasing them to mate with females in the wild. As they do not produce any offspring, the insect population declines over time.

A problem with this approach is that while mosquitoes create health problems for people, they also play important roles in various ecosystems, such as providing food for bats and other animals.  Eliminating mosquito populations on a large scale can trigger major changes in ecosystems.

Recently, an international team of scientists has synthetically engineered mosquitoes that halt the transmission of the dengue virus.  They genetically engineered mosquitoes with an antibody “cargo” that gets expressed in the female mosquitoes that spread the dengue virus.  Once the female mosquito takes in blood, the antibody is activated which hinders the replication of the virus and prevents its dissemination throughout the mosquito, thereby preventing its transmission to humans. Essentially, what the researchers have done is transfer genes from the human immune system to confer immunity to mosquitoes.  The researchers are testing methods to neutralize mosquitoes against other viruses they spread.

This opens up a whole new approach to interrupt mosquito-borne human diseases.  Mosquitoes are among the deadliest killers on the planet because they are the messengers that transmit deadly diseases.  Until now, the only real solution has been to kill the messenger.  The new approach may be a better way to deal with a serious problem.

**********

Web Links

Mosquitoes engineered to repel dengue virus

Photo, posted June 20, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Climate Change With Trees

August 20, 2019 By EarthWise Leave a Comment

We cut down forests all around the world for a myriad of reasons, including livestock grazing, agricultural production, timber, and urban development.  But what if we stopped cutting down forests for these things and additionally grew new forests on vacant lots and any other available parcels of land on earth?  What impact could this have on our survival? 

For the first time, scientists have quantified what impact this plan could have.  According to a new study by researchers at ETH Zurich – a university that specializes in science, technology, and engineering – the planet could support nearly 2.5 billion additional acres of forest without shrinking current cities and farms.  When all those acres of forest mature, the trees could store an extra 200 gigatons of carbon.  This reforestation could stave off the most devastating impacts of global climate change. 

Russia could restore the most acres of forest – 373 million acres to be precise – followed by the United States with 255 million acres and Canada with 193 million acres.  Australia, Brazil, and China also have large areas well-suited for forest restoration. 

The average global temperature has risen by 1.8 degrees Fahrenheit since the start of the industrial age with its surge in greenhouse gas emissions.  Temperatures are projected to rise even more in the coming years as the planet continues to warm.   

Trees absorb CO2 from the atmosphere and store it in their roots and branches.  The absorbed carbon becomes part of the soil when trees die and decompose, and it can linger there for millennia depending on things like temperature and soil management.  Trees are critical in the fight against climate change. 

**********

Web Links

How trees could save the climate

Photo, posted June 18, 2011, courtesy of K.W. Barrett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Beaches With Seagrass

February 22, 2019 By EarthWise Leave a Comment

Almost a quarter of the Gross Domestic Product of places around the Caribbean Sea is earned from tourism.  Preserving the beaches in the region is an economic imperative.  With increasing coastal development, the natural flow of water and sand is disrupted, natural ecosystems are damaged, and many tropical beaches simply disappear into the sea.

With such high stakes, expensive coastal engineering efforts such as repeated replenishing of sand and the construction of concrete protective walls are common strategies.  Rising sea levels and increasingly powerful storms only increase the threat to tropical beaches.

Researchers from The Netherlands and Mexico recently published a study in the journal BioScience on the effectiveness of seagrass in holding onto sand and sediment along shorelines.

Seagrasses are so-named because most species have long green, grass-like leaves. They are often confused with seaweeds but are actually more closely related to flowering plants seen on land. Seagrasses have roots, stems and leaves, and produce flowers and seeds. Seagrasses can form dense underwater meadows and are one of the most productive ecosystems in the world. Seagrasses provide shelter and food to an incredibly diverse community of animals, from tiny invertebrates to large fish, crabs, turtles, marine mammals and birds.

The researchers performed measurements of the ability of seagrass along Mexico’s Yucatan Peninsula coastline to keep sand in place and prevent erosion.  They found that the amount of erosion was strongly linked to the amount of vegetation.  Quite often, seagrass beds have been regarded as a nuisance, rather than a valuable asset for preserving valuable coastlines.  The study opens opportunities for developing new tropical beach protection schemes in which ecology is integrated into engineering solutions.

**********

Web Links

Seagrass Saves Beaches and Money

Photo, posted October 13, 2010, courtesy of NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electricity From A Bionic Mushroom

December 28, 2018 By EarthWise Leave a Comment

https://earthwiseradio.org/wp-content/uploads/2018/12/EW-12-28-18-Electricity-from-a-Bionic-Mushroom.mp3

In an engineering feat straight out of a weird science-fiction story, researchers at Stevens Institute of Technology in New Jersey have taken an ordinary white button mushroom and used 3D printing technology to coat it with graphene microribbons and cyanobacteria to produce a device that generates electricity.

[Read more…] about Electricity From A Bionic Mushroom

A Plane With No Moving Parts

December 11, 2018 By EarthWise 1 Comment

https://earthwiseradio.org/wp-content/uploads/2018/12/EW-12-11-18-A-Plane-With-No-Moving-Parts.mp3

Airplanes have been with us for more than a century and they fly with the help of propellers, turbine blades or fans that noisily move them through the air.  Recently, MIT engineers have built and flown a plane with no moving parts.

[Read more…] about A Plane With No Moving Parts

A Robot Fish

April 30, 2018 By EarthWise Leave a Comment

https://earthwiseradio.org/wp-content/uploads/2018/04/EW-04-30-18-A-Robot-Fish.mp3

Scientists studying marine life have to figure out ways to get cameras into areas that are too dense or dangerous for people to enter.   This often means sending delicate equipment into places where collisions are both likely and damaging and that equipment is generally tethered to ships or other objects.  To really see what is going on in the underwater world, a better approach is needed.

[Read more…] about A Robot Fish

The Tiny Country That Feeds The World

October 3, 2017 By EarthWise Leave a Comment

https://earthwiseradio.org/wp-content/uploads/2017/10/EW-10-03-17-The-Tiny-Country-that-Feeds-the-World.mp3

The Netherlands is a small, densely populated country with more than 1,300 inhabitants per square mile.  It lacks almost every resource one associates with large-scale agriculture.  Nevertheless, it is the number two exporter of food in the world, second only to the United States, which is almost 300 times bigger.  The Dutch lead the world in exporting tomatoes, potatoes and onions and produce many other crops as well. 

[Read more…] about The Tiny Country That Feeds The World

A Floating Wind Farm

September 5, 2017 By EarthWise

https://earthwiseradio.org/wp-content/uploads/2017/09/EW-09-05-17-A-Floating-Wind-Farm.mp3

Offshore wind farms are becoming increasingly important around the world.  Europe has thousands of wind turbines off its coasts generating more and more of its power.  The first offshore wind farm in the U.S. opened for business last year and more are on the way.

[Read more…] about A Floating Wind Farm

Clean Air And Energy

July 7, 2017 By EarthWise

https://earthwiseradio.org/wp-content/uploads/2017/07/EW-07-07-17-Clean-Air-and-Energy.mp3

Researchers in Belgium have engineered a device that uses sunlight to purify polluted air and, in the process, produces hydrogen gas that can be stored and used for power.  Two teams of researchers separately investigating processes for air purification and hydrogen production combined their efforts to create the new device.

[Read more…] about Clean Air And Energy

Climate Engineering

January 11, 2017 By EarthWise

https://earthwiseradio.org/wp-content/uploads/2016/12/EW-01-11-17-Climate-Engineering.mp3

With the forthcoming administration change, it appears that the federal government is likely to start backing away from tackling climate change and may even be obstructive towards efforts to mitigate the growing problem of greenhouse gas emissions.

[Read more…] about Climate Engineering

Student-Led Solar Revolution

December 2, 2016 By WAMC WEB

https://earthwiseradio.org/wp-content/uploads/2016/12/EW-12-02-16-Student-Led-Solar-Revolution.mp3

College students have often spearheaded uprisings and revolutionary ideas.   A group of BYU engineering students is trying to start a solar-cell revolution.

[Read more…] about Student-Led Solar Revolution

Go With The Flow

February 24, 2016 By WAMC WEB

https://earthwiseradio.org/wp-content/uploads/2016/02/EW-02-24-16-Go-With-The-Flow.mp3

Have you ever wondered what happens when a fish encounters a dam or a culvert? Too often, these structures are barriers to breeding and nursery sites, feeding grounds, and vital genetic mixing. In a warming world, barriers also prevent fish from seeking refuge as stream temperatures change.

[Read more…] about Go With The Flow

Primary Sidebar

Recent Episodes

  • Energy From Rice Straw | Earth Wise
  • California Flooding | Earth Wise
  • The Race For EV Batteries | Earth Wise
  • Turning Carbon Into Stone | Earth Wise
  • Tracking Global Forest Changes | Earth Wise

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)

Copyright © 2023 ·