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Wastewater As A Freshwater Source | Earth Wise

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Water covers three-quarters of our planet, but freshwater – the water we drink, bathe in, and irrigate crops with – comprises only 3% of the world’s water and much of that is frozen in glaciers or otherwise unavailable.  Nearly 3 billion people suffer from water scarcity for at least some of the year.

Natural freshwater sources – lakes, rivers, and groundwater – are under stress from the effects of climate change and from the increasing demands of city populations.  The wastewater treatment plants in large cities represent a significant potential water source provided that sustainable and economical technologies to produce it can be developed.

Researchers at Lehigh University in Pennsylvania have patented an innovative ion exchange desalination process that is a legitimate candidate to transform wastewater into usable water.

Existing large-scale desalination systems make use of semipermeable reverse osmosis membranes that require an energy source to run the system.  The Lehigh process, which they call HIX-Desal, harnesses the unique chemistry of carbon dioxide to take the place of the energy used in reverse osmosis systems. 

Tests of the new system show that the salinity of treated wastewater can be reduced by more than 60% by the HIX-Desal process without requiring any reverse osmosis.  At an Allentown, Pennsylvania water treatment plant where the system was tested, the researchers estimated that using the system could save about a million kWh per day in electricity usage, enough energy to power 94 homes for a year.

With this system, waste carbon dioxide from landfills or turbine exhaust can be used to desalinate municipal wastewater.  It could be the basis of a circular economy.

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Desalination tech uses CO2 to tap into municipal wastewater as alternative freshwater source

Photo, posted November 28, 2020, courtesy of Richard Ricciardi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon From 25 Cities | Earth Wise

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There are roughly 10,000 cities in the world, defined as places with at least 50,000 inhabitants with a sufficient population density.  Roughly half the world’s population lives in cities.

Urban carbon emissions are one of the world’s biggest problems with respect to the climate.  A new study has determined that just 25 cities globally are responsible for 52% of urban greenhouse gas emissions.

The study gathered data on greenhouse gas emissions in 167 cities in 53 countries.  The results were that megacities in Asia, such as Shanghai and Tokyo, were among the biggest total emitters, and that major cities in Europe, the US, and Australia tended to have larger per capita emissions.  Several Chinese cities, however, matched levels seen in developed countries.  Researchers tracked emissions over time in 42 of the cities studied.  Some cities saw declining emissions in the period between 2005 and 2016.  These included Oslo, Houston, Seattle, and Bogota.  Others saw large increases, including Rio de Janeiro, Johannesburg, and Venice.

The largest sources of emissions are power generation, industry, and transportation.  In a third of the cities, road transportation alone accounted for over 30% of emissions.  (Railways, waterways, and aviation combined only accounted for less than 15% of total emissions).

Half of the world’s population lives in cities, but cities are responsible for more than 70% of greenhouse gas emissions.  Thus, cities have a big responsibility for the decarbonization of the global economy.  Of the 167 cities in the study, 113 have set emission-reduction targets.  But as the study shows, cities have much more work to do to meet the goals of the Paris Climate Agreement.

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Two Dozen Large Cities Produce 52 Percent of Urban Carbon Emissions

Photo, posted December 1, 2017, courtesy of Hector Galbis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Soaring Heat And Inner-City Neighborhoods | Earth Wise

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The record-breaking heatwaves this summer have exposed the special vulnerability inner cities have to the effects of summer heat.  Climate change has exacerbated and supercharged heatwaves, as was seen in Seattle and Portland in late June.

Urban cores can be 10 degrees or more warmer than the surrounding countryside.  The urban heat island effect is a result of how cities are built, with so much pavement, so many buildings, and not enough trees.  On top of this, decades of disinvestment in neighborhoods where people of color live have left them especially vulnerable to heat as their homes are not able to cope with it.

In New York City, some residents of Hunts Point in the Bronx keep lists of neighbors they check on to help keep the most vulnerable alive during heat waves.  The city has subsidized 74,000 air conditioners for low-income, elderly residents, and is spending millions to plant trees.  In Phoenix, the hottest big city in the country, officials are working to develop new models for cooler public housing and cooling for streets and pedestrian corridors.

A study, published in 2020, looked at the linkage between higher heat island temperatures and past practices of redlining, where home loans and insurance were unavailable to people in neighborhoods of color.  In 94 of 108 communities studied, the formerly redlined neighborhoods had higher surface temperatures.

Cities are confronted with two heat problems:  emergencies that require immediate action to save lives, and long-term issues related to combating soaring temperatures in heat islands strengthened by global warming. In many cases, cities are not prepared for either problem.  Dealing with and adapting to heat is essential to the long-term viability and quality of life in our cities.

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A Triple Whammy Has Left Many Inner-City Neighborhoods Highly Vulnerable to Soaring Temperatures

Photo, posted May 27, 2014, courtesy of Dan DeLuca via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is Peak Oil Here? | Earth Wise

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For many years there has been talk of “peak oil”, the point at which rising world oil consumption would peak and then start declining.  Some analysts have been predicting that this could happen by the 2030s.   But the coronavirus pandemic drove a 9% slump in oil demand in 2020 that some economists are saying might never be entirely reversed.

There are three major forces driving down the world’s appetite for oil:  decarbonization of economies to meet the goals of the Paris climate agreement, declining demand for oil as renewable energy sources and electric vehicles are increasingly adopted, and detoxification as cities act to curb particulates and emissions from burning petroleum.

The largest single factor is electric vehicles.  Automobiles currently consume almost half of the world’s oil.  As of the end of 2020, there were an estimated 10 million electric cars as well as more than 600,000 electric buses and trucks.  This is still less than 1% of all vehicles, but 5% of all new cars being bought are now electric and the number is growing rapidly.  Experts estimate that nearly a quarter of global car sales will be electric vehicles by 2025 and many car manufacturers are promising to sell only electric cars within the next 10 years.

The decline in oil demand is pretty much inevitable at this point.  The main question is how quickly it will happen.  Road transport makes up 48% of global oil demand, petrochemicals account for 14%, aviation 7%, and shipping 6%.  Ultimately all these things are likely to diminish over time. 

Only time will tell, but the long-awaited arrival of peak oil may already have happened.

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Amid Troubles for Fossil Fuels, Has the Era of ‘Peak Oil’ Arrived?

Photo, posted April 14, 2019, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Importance Of Urban Green Spaces | Earth Wise

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Projections are that 68% of the global population will be living in cities by 2050.  It is therefore not surprising that urban green spaces are critically important for promoting mental and physical well-being.

An international study, published in Science Advances, took soil samples from different types of urban green spaces and comparable neighboring natural ecosystems in 56 cities from 17 countries across six continents.

The study concluded that even roadside plantings contribute a range of important microbial communities that are critical for sustaining productive ecosystems services, such as filtering pollutants and sequestering carbon dioxide.

Parks and gardens constitute most of the open spaces available for recreational activities in cities and play important roles in curbing pollution, reducing noise, and lowering air temperatures.

In addition, human exposure to soil microbes has been shown to be beneficial to human health by promoting effective immunoregulation functions and reducing allergies. The study found that city parks and even roadside plantings support a great variety of different microbes that are different from natural ecosystems. 

We think of roadsides as being barren but the vegetation along footpaths and roadsides are important microbial habitats.  Some European cities, such as Bern in Switzerland, have instituted policies to protect the natural vegetation along footpaths and roadsides.

The new study is a part of a series of research efforts looking at the important of green spaces for ecosystem health.  As the world becomes increasingly urbanized, every bit of greenery in cities and highways is important and is needed for sustaining a healthy environment.

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Every spot of urban green space counts

Photo, posted June 3, 2013, courtesy of Manuel MV via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Hottest June | Earth Wise

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A series of heatwaves from coast to coast caused June 2021 to be the hottest June on record in the U.S. The average June temperature across the contiguous U.S. was 72.6 degrees Fahrenheit, making it the hottest June in 127 years of record keeping and breaking the previous record set in 2016 by nearly a full degree. Eight states had their hottest June on record and six others marked their second hottest June.

One of the most extreme heatwaves in modern history impacted the Pacific Northwest of the U.S. and western Canada late in the month.  Temperature records were not merely broken in the region; they were smashed over an incredibly hot four-day period from June 26th through June 29th when all-time records over 100 degrees were set at dozens of locations.

Portland, Oregon’s average high temperature over this period was 112 degrees, breaking the previous 3-day record by an amazing 6 degrees.  The high on June 28th was 116 degrees, an all-time record for the city.  Seattle set back-to-back all-time heat records of 104 on June 27th and then 108 on June 28th.  In the previous 126 years, Seattle had only hit 100 degrees three times.  It reached that mark 3 days in a row in June.

Crossing the border, the town of Lytton, British Columbia reached a temperature of 121 degrees on June 29th, the third day in a row in which the town registered a new all-time high temperature ever measured in Canada.  To put this in perspective, this temperature is hotter than has ever been recorded in Las Vegas.

June was a hot month indeed.

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June 2021 was the hottest June on record for U.S.

Astounding heat obliterates all-time records across the Pacific Northwest and Western Canada in June 2021

Photo, posted July 7, 2021, courtesy of Poyson / GPA Photo Archive via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Strategies To Cool Off Cities | Earth Wise

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Heatwaves in cities are becoming increasingly common and increasingly intense.  The warming climate is a big factor, but it is the nature of our cities that really drives up temperatures.  Solar radiation stored throughout the day on asphalt and buildings is released slowly during the night, which generates significant heat stress.

A study carried out by a major Barcelona university and published in the journal Urban Climate looked at the effectiveness of various ways to mitigate the heating effects in cities.  In particular, the study examined the effects of the use of white roofs on buildings and the expansion of urban green areas with daily irrigation in the Barcelona metropolitan area.  It simulated various scenarios incorporating combinations of these two mitigation strategies.

The strategy with the greatest impact was a combination of the use of both white roofs and the addition of six urban parks, which is a target set by the Barcelona Urban Master Plan.  This scenario resulted in an average temperature reduction of 2.25 degrees Fahrenheit.  The maximum reduction occurs during the mid-afternoon with a reduction of 7 degrees and the combination still provides more than 3 degrees of reduction at 9 pm.  Reducing temperatures this way also results in a reduction in energy consumption, with 26% less spending on air conditioning.

The 2-pronged strategy combines the benefits of reducing the temperature at night due to more urban green areas with the reduction of daytime heat due to both the increased reflectivity of white roofs as well as the irrigation of the green areas.

The study demonstrates how modeling efforts can help urban planners to counteract the impacts of heatwaves, which are likely to increase with climate change and intensification of urbanization.

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White roofs and more green areas would mitigate the effects of heat waves in cities

Photo, posted January 16, 2011, courtesy of Sean MacEntee via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Deep Learning And Dirty Air | Earth Wise

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Poor air quality is a major global problem.  According to the World Health Organization, exposure to air pollution is linked to the premature deaths of an estimated seven million people every year.  In fact, 9 out of 10 people breathe air that contains more pollutants than what the WHO considers safe.  Air pollution is the fourth largest threat to human health, trailing only high blood pressure, dietary risks, and smoking.

But predicting pollution levels at a given place and time remains challenging.  According to a new study recently published in the journal Science of the Total Environment, scientists are turning to deep learning to improve air quality estimates. 

According to researchers, satellite observations and ground observations both measure air pollution, but both have major limitations.  For example, satellites may collect data at the same time and at the same location each day, but they miss how emissions may vary throughout the day.  Ground-based observations from weather stations do continuously collect data, but they only do so in a limited number of locations.    

As a result, scientists have turned to deep learning – a type of machine learning – to analyze the relationship between satellite and ground-based observations of nitrogen dioxide around Los Angeles.  Nitrogen dioxide is associated with emissions from traffic and power plants.  The researchers were able to rely on the learned relationship to take daily satellite observations and create hourly estimates of atmospheric nitrogen dioxide levels in approximately three mile grids.     

According to the research team, this study could be repeated for other greenhouse gases, and applied to different cities and regions – or even whole continents. 

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Scientists turn to deep learning to improve air quality forecasts

Air Pollution

Photo, posted November 4, 2019, courtesy of Ninara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Residential Gardens And Pollinators | Earth Wise

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A new study led by the University of Bristol in the UK measured for the first time how much nectar is produced in urban areas to gauge the role of residential gardens in providing nutrients for pollinators.  They discovered that home gardens accounted for the vast majority of the crucial nutrients for pollinators; in fact, some 85% on average.

The study found that gardens generated a daily average of about a teaspoon of the unique sugar-rich liquid found in flowers which pollinators drink for energy.  A teaspoon sounds like very little, but it is enough to feed thousands of bees.

The research examined nectar production in four major UK towns and cities and measured nectar production in nearly 200 species of plants.  The results were that the nectar supply in urban landscapes is more diverse than in farmland and nature reserves.   In addition, gardens are critical because they produce the most nectar per unit area of land and actually cover the largest area of land in the cities studied.  In those cities, nearly a third of the land comprised domestic gardens, which is six times the area of parks and 40 times the area of small green allotments.

The upshot of the research is that home gardeners have a huge role to play in pollinator conservation.  Without domestic gardens, there would be far less food for pollinators that include bees, wasps, butterflies, moths, flies, and beetles.  Thus, it is important for home gardeners to keep planting nectar-rich flowers, mow lawns less often to let dandelions, clovers, and daisies flourish, avoid harmful pesticides, and avoid covering gardens in paving, decking, or artificial turf.

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Pioneering research reveals gardens are secret powerhouse for pollinators

Photo, posted June 23, 2018, courtesy of Wolfferl via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Compost And Landfills | Earth Wise

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Composting is popular as a way to keep solid waste out of landfills and many people turn much of their kitchen waste into rich soil amendments.   Cities and towns across the country have composting programs that collect waste from residents to produce large quantities of compost rather than adding the waste to landfills.  A new study from North Carolina State University looked into the environmental benefits of actually using compost at landfills.

Most municipal composting programs require that the compost they produce gets used “beneficially”.  The new research shows that using compost as an alternative daily cover at landfills is competitive and often superior to the use of compost as a soil amendment in terms of its environmental benefits.

Landfills apply a layer of daily cover to reduce odors, reduce windblown debris, and keep vermin out of landfill waste.  Federal regulations require six inches of soil as a daily cover.

Compost from food waste in particular is not always suitable for soil amendment in gardens and agricultural fields because it often contains broken glass and other contaminants.

The North Carolina State study looked at the environmental impact of using compost as daily cover in landfills compared with its use as a soil amendment.  They looked at global warming potential, acidification potential, eutrophication (which is the amount of nutrients released to ground and surface water), cumulative energy demand, and the depletion of resources.

The study concluded that using compost as landfill daily cover is environmentally superior with regard to eutrophication, acidification, and global warming potential.  On the other hand, soil amendment was better in terms of resource depletion and cumulative energy demand.

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Applying Compost to Landfills Could Have Environmental Benefits

Photo, posted April 22, 2008, courtesy of Alachua County via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pandemic Lockdowns And Carbon Emissions | Earth Wise

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The early months of the COVID-19 pandemic saw many human activities reduced to a fraction of what they were previously.  Notably, air pollution in major cities was dramatically lower than it had been in decades.  Now, a new study has looked at the effect of the pandemic shutdowns on carbon dioxide emissions.

An international team of climate scientists has published an assessment of carbon dioxide emissions by industry, transportation, and other sectors from January through June.  According to their measurements, this year’s pandemic lockdowns resulted in a 9% decline in emissions from 2019 levels.

An earlier study reported a 17% drop in CO2 emissions, but the new study was more comprehensive and detailed.

The new data includes estimates of day-by-day, sector-specific and country-level differences in CO2 emissions derived from frequently updated data sources, some of which are nearly in real-time.  It tracks the effects of COVID-19-related disruptions of human activities in China starting in February and in the United States and Europe in March through May.

The data revealed the resumption of emissions in many regions, such as in China, where they are now back to pre-pandemic levels.  Emissions in the Americas and Europe have been slower to recover, especially in the US, where COVID-19 hotspots are continuing to emerge. 

The reduction in carbon emissions has been due mostly to transportation with fewer people driving to work and traveling by air.  Even by June, when lockdowns were easing, global emissions were still significantly reduced.  In any case, a pandemic is a highly undesirable and unwelcome way to reduce carbon emissions, but the data from this year does show that it is effective.

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Pandemic lockdowns caused steep and lasting carbon dioxide decline

Photo, posted August 7, 2020, courtesy of Michael Mueller via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Paint For Cooler Buildings | Earth Wise

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A research team led by scientists at UCLA have developed a super-white paint that reflects as much as 98% of incoming heat from the sun.  Such paint, if used on rooftops and other parts of buildings, could have a major impact on reducing the costs of keeping buildings cool.

Passive daytime radiative cooling is a well-known method to keep buildings cooler.  By having building surfaces reflect sunlight and radiate heat into space, building temperatures can be significantly lowered.  This in turn cuts down on air conditioner use and associated carbon emissions.

A roof painted white will result in lower indoor temperatures than a darker roof.  But a white roof will do even more:  it can reject heat at infrared wavelengths that are invisible to our eyes.  This results in even more radiative cooling.

The best performing white paints currently available reflect about 85% of incoming solar radiation.  The rest is absorbed by materials in the paint.  The new research has identified simple modifications in paint ingredients that lead to a major increase in reflectivity.

Current reflective white paints use titanium dioxide, which absorbs UV radiation and therefore heats up under sunlight.  The researchers studied replacing it with other substances such as barite – an artist’s pigment – or with powdered Teflon, both of which allow the paint to reflect more of the sun’s radiation. 

Many cities are encouraging the use of cool-roof technologies on new buildings.  Using the most reflective coatings possible on rooftops, if applied on a sufficiently large scale, could have a real impact on climate change as well as saving significant amounts of energy used for running air conditioners in buildings.

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UCLA-led Team Develops Ways to Keep Buildings Cool with Improved Super White Paints

Photo, posted August 15, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Benefits Of A Zero-Emissions Boston | Earth Wise

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Many countries, states, and cities around the world have set goals to become carbon neutral, typically by the year 2050.  These goals are based on the desire to mitigate the effects of climate change that are steadily increasing as a result of the buildup of carbon dioxide in the atmosphere.  But reducing emissions is not just a way to combat climate change, it can also be a major contributor to improved public health.

The City of Boston has set a goal to become carbon neutral by 2050.  A new study by the School of Public Health at Boston University published in the journal Environmental Research Letters looked at the consequences of eliminating fossil fuel emissions in the greater Boston area.

According to their modeling, eliminating emissions would save 288 lives a year by reducing fatal and non-fatal cardiovascular and respiratory illnesses.   The resulting decrease in medical costs and lost and reduced work could save $1.7 billion a year in Suffolk County and $2.4 billion a year for the entire 75-square-mile zone modeled in the study.

The study looked at the amounts of two air pollutants known to harm human health:  PM2.5 (particulates with a diameter of less than 2.5 microns) and ozone.  They compared the current levels of these pollutants to what would be present when contributions from motor vehicles, generators, rail, industry, oil- and gas-burning, shipping and boating, and residential wood fires were eliminated.

The study focused on the City of Boston’s climate action plan, but actions taken by Boston will not take place in a vacuum.  Many cities across the region are taking similar actions.  The overall results will come from the collective actions across New England.

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A Zero-Emissions Boston Could Save 288 Lives and $2.4 Billion Annually

Photo, posted August 31, 2019, courtesy of Eric Kilby via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Immersion In Nature Is Good for You | Earth Wise

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There is a growing body of research that shows that getting outdoors in nature can be good for people’s health and well-being. There are so many studies supporting this idea that policymakers, employers, and healthcare providers are increasingly considering this need for nature in how they plan and operate.

A new study of 20,000 people by researchers at the University of Exeter in the UK actually looked at how much exposure to nature was enough to make people say they feel healthy and have a sense of well-being.   The answer turned out to be 2 hours a week.  And the correlation was strong.  People who didn’t meet that threshold did not report the benefits.

Studies have shown that time in nature – as long as people feel safe where they are – is an antidote for stress.  It can lower blood pressure and stress hormone levels, reduce nervous system arousal, enhance immune system function, increase self-esteem, reduce anxiety, and improve mood.  Most of these studies are correlational rather than causal, but the results tend to be robust.

Given all this, cities are adding or enhancing parks, and schools and other institutions are being designed with large windows and access to trees and green space.  The Scandinavian tradition of “forest schools” – where learning takes place in natural settings outdoors -.is finding a home in the US.   Japanese researchers study the effects of “forest bathing”, a poetic term for walking in the woods.

With two-thirds of humanity projected to be living in cities by 2050, we are awakening to the idea that we need to be able to spend time in nature for our own wellbeing, even if it’s just a walk in a park.

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Ecopsychology: How Immersion in Nature Benefits Your Health

Photo, posted November 6, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising Seas Will Erase Cities

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According to new research, climate-driven sea level rise could affect three times more people by 2050 than previously thought.  This sobering assessment means some of the world’s great coastal cities, including Bangkok, Shanghai, Mumbai, Basra, Alexandria, and Ho Chi Minh City, could be in big trouble.   

Scientists have always relied on land elevation data to determine the effects of sea level rise over large areas.  But standard elevation measurements using satellites struggle to differentiate the true ground level from the tops of trees or buildings.  The authors of the paper developed a more accurate way to calculate land elevation by using artificial intelligence to determine the error rate and to correct for it.  The new findings revealed that 150 million people – three times more than previously thought – are now living on land that is projected to be below the high-tide line by the middle of this century. 

Eight Asian nations – China, Bangladesh, India, Vietnam, Indonesia, Thailand, the Philippines, and Japan – account for about 70% of the people living on at-risk land. 

More than 20 million people in Vietnam, including much of Ho Chi Minh City, live on land that will be inundated by 2050.  In Thailand, more than 10% of its citizens, including much of Bangkok, currently live on land imperiled by projected sea level rise. 

This new research was produced by Climate Central, a New Jersey-based science organization, and was recently published in the journal Nature Communications. 

Sea level rise is clearly not just an environmental problem.  It’s a humanitarian crisis.

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New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding

Rising Seas Will Erase More Cities by 2050, New Research Shows

Photo, posted December 18, 2009, courtesy of Misko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of Zero-Carbon Cities

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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.

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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.

Electric Buses In Latin America

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Latin America has become increasingly urbanized.  In fact, about 80% of the region’s population lives in cities today and by 2050, that figure could climb to 90%.  Transportation is the largest and fastest-growing source of energy-related emissions in Latin America and accounts for about a third of all of the region’s carbon dioxide emissions. 

Private vehicle ownership is rising in Latin America but at the same time, the region’s rapidly growing cities have increased demand for buses, taxis, and motorcycles.  Currently, an estimated 64,000 people die prematurely every year in Latin America and the Caribbean as a result of air pollution, which is mostly caused by transportation emissions.

Given this situation, major cities across Latin America – from Colombia to Argentina – are starting to adopt electric bus fleets.   Latin America actually has the highest use of buses per person globally.  So, the transition to electric buses is an important step toward meeting climate targets, cutting fuel costs, and improving air quality.

Medellin, Colombia – whose metropolitan area has 3.7 million people – has started to add electric buses to its fleet, the rest of which runs on natural gas.  When new units arrive from China later this year, Medellin will have the second largest electric bus fleet in Latin America, after Santiago, Chile. 

Worldwide, 425,000 electric buses are in operation, 99% in China.  Europe has a couple of thousand while the United States has only 300.  But going forward, and especially in Latin America, electric buses are the wave of the future.  Estimates are that there will be 1.3 million on the roads by 2040.

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An Increasingly Urbanized Latin America Turns to Electric Buses

Photo, posted April 22, 2018, courtesy of Hans Johnson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Which Cities To Save From The Changing Climate

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After several years of brutal flooding and hurricanes in the U.S., a distressing debate is emerging:  if there is not enough money available to protect every coastal community from the effects of global warming, how do we decide which ones to save first.

Recent research looked at the costs involved in providing basic storm-surge protection in the form of sea walls for all coastal cities with more than 25,000 residents.  That number was $42 billion.  Expanding the list to include communities smaller than 25,000 people would increase that cost to more than $400 billion.   Realistically, that is just not going to happen.

This particular study only looked at sea walls and no other methods for minimizing flood risk, such as moving homes and businesses away from the most flood-prone areas.   It also didn’t look at additional and costlier actions that will be required even with sea walls, such as revamping sewers, storm water, and drinking water infrastructure.

The facts are that many cities, especially small ones, will not be able to meet the costs facing them.  Those that can’t will depend on federal funding.  But even optimistically large proposals for federal infrastructure spending are likely to fall far short of the vast need.  Ultimately, the money will end up being spent where it can do the most good – even if it means that some places are left out.

But what criteria will be used to direct the money?  Economic value?  Historic significance?  Population?  Political influence?

This is a looming and massive issue whose chief obstacle may be that many officials refuse to acknowledge that it is happening.  This is the next wave of climate denial – denying the costs that we are all facing.

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With More Storms and Rising Seas, Which U.S. Cities Should Be Saved First?

Photo, posted October 31, 2018, courtesy of Patrick Kinney via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe Is Warming Faster Than Predicted

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A new study has found that Europe is warming faster than even climate models projected.  The number of summer days with extreme heat in Europe has tripled since the 1950s, while the number of days with extreme cold has decreased by factors of two or three depending on the region.

According to climate scientists at the Swiss Federal Institute of Technology in Zurich, the climate trends are much larger than what would come from natural variability and are a clear signal of climate change.  Extremely hot days in Europe have become hotter by an average of more than 4 degrees Fahrenheit while extremely cold days have warmed by more than 5 degrees.  The research examined data from weather stations across Europe from 1950 to 2018.  Over 90% of the stations recorded increasing temperatures over time, a percentage much too high to be purely from natural climate variability.  The results also showed that the region was warming even faster than climate models projected.

The research results come after an extremely hot summer in Europe.  Southern France hit 114.8 degrees, a new record, in June.  Germany, the Netherlands, and Belgium all recorded all-time national temperature highs.  The National Oceanic and Atmospheric Administration recently announced that July was the hottest month ever recorded.

European summers and winters will only grow hotter in the coming years as climate change accelerates.  The rapidly increasing temperatures will impact cities and people that are unprepared for them and pose real risks for residents in the coming decades.  Extreme heat is dangerous because it stresses the human body, potentially leading to heat exhaustion or heat stroke.

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Europe warming faster than expected due to climate change

Photo, posted July 30, 2011, courtesy of Marcel de Jong via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Cost Of Rising Seas

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Coastal cities in the United States are grappling with the need for extensive infrastructure projects to protect against rising seas and worsening storms.  The cost of these projects will be enormous, and it is unclear how to pay to them.

Boston has many neighborhoods in low-lying areas, and it is estimated that $2.4 billion will be needed to protect the city from flooding.  The city abandoned plans to build a harbor barrier that would have cost $6 to $12 billion because it was economically unfeasible.

Charleston, South Caroline needs $2 billion to reduce flooding that occurs regularly during high tides.  The Houston, Texas area needs $30 billion to provide protection against a 100-year flood.  Hurricane Harvey caused $125 billion in damages in Texas in 2017.  New York City is considering a $10 billion storm surge barrier and floodgates to shield parts of the city from rising waters.

Florida faces the greatest exposure to flooding with an estimated $76 billion in costs to address some of its problems.

At the federal level, multiple agencies represent potential funding sources, but none offer the kind of money required to address the need.  This places a heavy burden on state and local governments.  Various states have passed legislation related to shoreline resiliency and flood abatement, but relatively little funding has been approved.  Some bond measures have passed, but the totals are small compared with what is needed.

Educating people about the costs of not doing anything or not doing enough soon enough is essential.  As Hurricane Katrina demonstrated, not spending a large amount of money on resilience can result in having to spend a colossal amount of money on recovery.

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Who Will Pay for the Huge Costs of Holding Back Rising Seas?

Photo, posted December 26, 2013, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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