Earth Wise

A look at our changing environment.

You are here: Home / Archives for traffic

traffic

Alaskan Icemageddon | Earth Wise

By 1 Comment

December saw some wild weather in Alaska.  A combination of record high temperatures and torrential rainstorms resulted in the coining of the term “Icemageddon” to describe what was going on with the weather.

Kodiak Island in southern Alaska saw a high temperature of 67 degrees on December 26, which was warmer than it was in Southern California that same day.  This set an all-time record for the warmest December day in Alaska.  Such a high temperature is amazing considering how little sunlight Alaska gets at this time of year.  And with warmer air comes wetter air, as the atmosphere is capable of holding more water vapor as temperatures increase.

As a result, that same day saw the interior of the state get an inch of rain in just a few hours, something that hadn’t happened for decades.  But then, when temperatures plummeted again, all that rainwater froze.

Huge sheets of ice blocked roads and choked traffic in Fairbanks, Alaska’s second largest city.  Indeed, it was the state’s transportation department that came up with the term icemageddon to describe the situation.

The extreme warmth in December is related to the same weather pattern that brought cold, wintry weather to the Pacific Northwest and Northern California.  Those weather conditions resulted in hundreds of cancelled flights in Seattle, where temperatures dropped into the 20s, and in massive amounts of snowfall in the Sierra Nevada mountains in California.  A strong area of high pressure anchored in the Northern Pacific resulted in a clockwise flow around it drawing warmer, more tropical air from the Pacific up to Alaska.

Climate change continues to push the envelope on what sort of weather is possible all over the world.

**********

Web Links

Alaska faces ‘Icemageddon’ as temperatures swing wildly

Photo, posted April 30, 2015, courtesy of Naql via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reduced Air Travel And Weather Forecasts | Earth Wise

By Leave a Comment

There have been countless stories about the major and minor changes in the world caused by the Covid-19 pandemic.  A few of those changes, such as reductions in pollution and traffic, have been positive.  Most have been decidedly negative.

One of the stranger things that has happened is that the pandemic has affected the quality of weather forecasting by sharply reducing the amount of atmospheric data routinely collected by commercial airliners.

It turns out that atmospheric observations from passenger and cargo flights are among the most important data used in weather forecasting models.  These observations are made by instruments aboard thousands of airliners, mostly based in North America and Europe.  The observation program has been in place for decades.  The data is transmitted in real time to forecasting organizations around the world, including the National Weather Service.  About 40 airlines participate in the program, which has equipment aboard about 3,500 aircraft.  Here in the US, Delta, United, American, and Southwest Airlines participate, as do UPS and FedEx.

During the first few months of the pandemic, air traffic declined by 75% or more worldwide.  As a result, atmospheric observations dropped by the same percentage.  A government research study showed that when weather forecasting models receive less data on temperature, wind, and humidity from aircraft, the accuracy of forecasts was reduced.

The amount of data from aircraft has increased in recent months as air travel has picked up to roughly 50% of pre-pandemic levels.  So, the observation program is on the mend.  Nonetheless, impaired weather forecasting is just another unexpected result of the global pandemic.

**********

Web Links

Slump in Air Travel Hindered Weather Forecasting, Study Shows

Photo, posted July 15, 2017, courtesy of Daria Nepriakhina via Flickr. Photo by Photo by Daria / epicantus.

Earth Wise is a production of WAMC Northeast Public Radio.

Permanent Time Observation | Earth Wise

By Leave a Comment

Americans have debated the value of daylight savings time going all the way back to Benjamin Franklin.  As a country, we adopted the practice of changing our clocks twice a year in 1918.

Since the energy crisis of the 1970s, there have been a number of initiatives aimed at making daylight savings time permanent.  However, there is also a growing movement to eliminate the practice entirely.

In August, the American Academy of Sleep Medicine published a position statement calling for the abolishing of daylight savings time in favor of fixed, national, year-round standard time.

The statement describes the adverse effects of the annual abrupt switch to daylight savings time, which range from increased risk of stroke and hospital admissions to sleep loss and increased production of inflammatory markers, which are one of the body’s responses to stress.  It also cites studies that show that traffic fatalities increase by as much as six percent in the first few days following the change to daylight savings time.  Other research shows that there is an 18% increase in adverse medical events related to human error in the week after switching to daylight savings time.

In July, a survey by the academy of more than 2,000 U.S. adults found that 63% support the elimination of seasonal time changes in favor of a national, fixed year-round time, and only 11% oppose the idea, but many of those in favor of the idea actually want permanent daylight savings time.

The sleep academy contends that permanent standard time is the best choice to most closely match our circadian sleep-wake cycle while daylight saving time results in more darkness in the morning and more light in the evening, disrupting the body’s natural rhythm.

Residents of Arizona and Hawaii get to sit out this debate since they don’t change their clocks.

**********

Web Links

American Academy of Sleep Medicine calls for elimination of daylight saving time

Photo, posted May 28, 2018, courtesy of Kis Akos via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shutting Down Pollution | Earth Wise

By Leave a Comment

With much of the country shut down as the coronavirus forces people to stay at home, there has naturally been a drastic reduction of traffic on roads and highways.   And with that decrease, there has been a dramatic reduction in pollution as well.

A satellite that detects emissions in the atmosphere linked to cars and trucks has observed huge declines in pollution in major metropolitan areas such as Los Angeles, Seattle, New York, Chicago, and Atlanta.

Los Angeles is infamous for its rush-hour traffic but that has pretty much ceased to exist. Similar changes can be seen in the San Francisco Bay Area, where nearly 7 million residents have been ordered to shelter in place.  New York City is less dependent on car travel than in other metro areas, but the shutdown of office buildings, schools, and restaurants has nonetheless resulted in a substantial reduction of traffic on the streets of the city.

While this sudden decline in air pollution over U.S. cities has some near-term health benefits, those benefits are likely to be fairly minor in the big picture.  When the coronavirus outbreak subsides and people are allowed to leave their homes and go back to their normal lives, air pollution will most certainly rebound to previous levels.  In any event, studies have shown that long-term exposure to air pollution has a larger impact on public health than any transient events.

Having much cleaner air for a while is certainly a good thing, but this shutdown is not a sustainable way to reduce air pollution and the long-term effects of the coronavirus crisis will certainly not be positive.

**********

Web Links

Traffic and Pollution Plummet as U.S. Cities Shut Down for Coronavirus

Photo, posted March 15, 2020, courtesy of Tom Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Costs And Reducing Emissions From Shipping | Earth Wise

By Leave a Comment

International shipping is a large and growing source of greenhouse gas emissions.  Maritime transport produces about a billion tons of CO2 annually, accounting for about 2.5% of global greenhouse gas emissions.  The environmental impact of shipping includes air pollution, water pollution, and even acoustic pollution.  In many coastal areas, ships are responsible for more than 18% of some air pollutants.  Overall, there are more than 100,000 transport ships at sea, of which about 6,000 are large container ships.

In recent years, the shipping sector has had both internal willingness and external pressure to reduce emissions, but shipping is a tough, competitive business and it isn’t easy to stay competitive and help protect the environment.

A recent study at Abo Akademi University in Finland has found that improved ship utilization rates and investments in environmentally sustainable technologies for enhanced energy efficiency would significantly reduce carbon dioxide emissions.  Of equal importance, those same measures would contribute to lowering of freight costs.

If the same cargo volume can be shipped using less fuel, shipping companies will gain major savings in terms of fuel costs.  Digitalization can provide valuable benefits.  For example, new digital planning and booking systems would enable smarter use of routes while also diminishing traffic with half-empty vessels or even ones with no cargo aboard.  Reducing such underutilization would improve the capacity utilization rate and eliminate emissions caused by so-called ballast traffic.

Global shipping continues to grow.  It is essential that it becomes smarter and more efficient to protect the environment and improve its economics.

**********

Web Links

Environmentally friendly shipping helps to reduce freight costs

Photo, posted February 18, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of Zero-Carbon Cities

By Leave a Comment

A new report issued by a coalition of 50 leading international institutions shows that low carbon initiatives in cities could reduce urban emissions by nearly 90% and support 87 million jobs worldwide by 2030.  The report finds that implementing low carbon measures in cities would be worth almost $24 trillion by 2050.

Cities are home to more than half the world’s population but produce 80% of gross domestic product and 75% of carbon emissions.  The research highlights the significant benefits carbon reduction can bring to cities in areas such as public health, job creation, and poverty alleviation.

The report shows that it is possible to cut 90% of emissions from cities using currently available technologies and practices including carbon savings from buildings, transportation, materials efficiency, and waste reduction.  Doing so would require an investment of nearly $2 trillion per year but would generate annual returns of nearly $3 trillion in 2030 and $7 trillion in 2050 based on cost savings alone.  Many low carbon measures would pay for themselves in less than five years, including more efficient lighting, electric vehicles, improved freight logistics, and solid waste management.

In addition to economic benefits, compact, connected and clean cities could provide a higher standard of living and greater opportunity for all.  These measures would also reduce air pollution, cut chronic traffic congestion, and improve worker productivity.

The report offers case studies from around the world where national and local governments have worked together to rapidly and profoundly transform their cities for the better within 20 or 30 years.

**********

Web Links

The benefits of investing in zero-carbon cities

Photo, posted September 8, 2018, courtesy of Steffen Flor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Weather-Responsive Traffic Signals

By Leave a Comment

We all spend time sitting at red lights – sometimes it seems like a whole lot of time.  There is a fair amount of science applied in the design of traffic signals that at least has the aim of easing congestion and improving traffic safety.

Signals in modern cities are timed using optimization models that analyze multiple factors including traffic volume and speed with the goal of safely getting as many vehicles as possible through intersections.  It sure doesn’t seem that way in many places, but that is the intent in any case.

But a real problem with these models is that they assume normal conditions including weather conditions.  In places that experience real winter conditions, the assumptions of traffic models fail.  If the road surface is covered with snow and ice and visibility is poor, variables like speed and stopping distances become very different.

Researchers at the University of Waterloo in Canada collected data from real-world intersections and ran computer simulations to determine the effects of adjusting traffic signal behavior in bad weather (as well as in the presence of other conditions such as accidents or construction.)  They found that such adjustments could reduce traffic delays by as much as 20%.   

Cities with computerized signal systems are already equipped to remotely and inexpensively adjust the timing of traffic lights.  To gain the benefits of smarter signals, there would need to be video cameras and a certain amount of artificial intelligence software that would be able to automatically tweak the timing of lights in response to traffic changes caused by weather, accidents or construction. 

It sounds like a great idea.

**********

Web Links

Weather-responsive intersections could ease traffic congestion

Photo, posted September 22, 2009, courtesy of Tristan Bowersox via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Traffic Jams In The Jet Stream

By Leave a Comment

Many extreme weather events are associated with unusual behavior by the jet stream.   Jet streams are the global air currents that circle the earth.  The meandering and speed changes in the jet stream affect weather and also play a big role in how long it takes aircraft to make their way across the country.  The behavior that leads to extreme weather events is known as “blocking” in which the meandering jet stream stops weather systems from moving eastward.

[Read more…] about Traffic Jams In The Jet Stream

Snow Leopards And Humans

By

Snow leopards are majestic animals native to Central Asia.  They roam the region’s rugged terrain, from Afghanistan to Kazakhstan and Russia in the north, and to India and China in the east.  Snow leopards are known for their thick white coat of fur with ringed black and brown spots.  These markings help camouflage the animals from their prey.  But the camouflage does little to protect snow leopards from one of their biggest threats: humans.

[Read more…] about Snow Leopards And Humans

WAMC Northeast Public Radio

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