population

More Troubles For Bees | Earth Wise

July 22, 2020 By EarthWise Leave a Comment

Beekeepers in the United States lost nearly 44% of their managed honeybee colonies from April 2019 to April 2020, according to the 14th annual nationwide survey conducted by the nonprofit Bee Informed Partnership. This was the second highest annual loss recorded since the surveys began.

The high loss rate over the past year was unusual in that winter losses were actually substantially lower than they have been in recent years. The winter losses were 22.2%, which is 15.5 points lower than last year and 6.4 points lower than the average over the past 14 years. On the other hand, summer losses were 32%, which is 12 points higher than last year and 10.4 points higher than the average.

In fact, the summer loss was the highest ever recorded and was only the second time that more bees were lost in the summer than in the winter.

Commercial beekeepers generally have lower losses than backyard and smaller operations. Commercial honeybee colonies pollinate $15 billion worth of crops in the United States every year, so the health of these colonies is a critical issue for domestic food production and supply.

Beekeepers began noticing dramatic losses in their colonies in the early 2000s and ever since then, state and federal agricultural agencies, university researchers, and the beekeeping industry have been working together to try to understand the reasons for the population decline and to develop approaches to reduce these losses.

Winter loss has previously been the main focus of management activities since that period of the year is thought to be the most challenging for bee colonies. This year’s results are driving a great deal of analysis of the possible causes for the dramatic summer colony losses. Whatever they turn out to be, they represent more troubles for bees.

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Odd Year for U.S. Beekeepers Who Reported Lower Winter Losses but Abnormally High Summer Losses

Photo, posted April 14, 2013, courtesy of Paul Rollings via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Emissions And The Coronavirus Shutdown | Earth Wise

June 10, 2020 By EarthWise Leave a Comment

With so much of industry and personal activity curtailed by coronavirus shutdowns across the globe, it is no surprise that greenhouse gas emissions have declined. According to new research published in the journal Nature Climate Change, average daily global greenhouse gas emissions declined 17% by early April compared to 2019 levels.

If the reopenings around the world continue and the world actually reaches pre-crisis levels by the middle of June, total CO2 emissions for the year would likely end up lower by about 4%. If various restrictions continue until the end of the year, total global emissions could decline by 7%.

The study analyzed emissions estimates for three levels of coronavirus shutdowns and across six sectors of the economy. It looked at trends in 69 countries, all 50 U.S. states, and 30 Chinese provinces, representing in total 86% of the world’s population and 97% of global CO2 emissions.

For the first 4 months of the year, emissions from industry declined 19%, the power sector 7%, and public buildings and commerce 21%, compared to last year. Unsurprisingly, home energy use actually went up by about 3%.

The findings of this study only represent the effects of a short-lived decline in emissions. As economies open back up, there is no doubt that greenhouse gas emissions will rise back to pre-Covid-19 levels.

The study also reveals that making real changes in emissions will require more than just behavior changes. Despite billions of people staying home, companies shut down, planes grounded, and cars off the road, we still managed to pump more than 80% of the usual amount of greenhouse gases into the air for the first quarter of the year.

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Global Emissions Fell 17 Percent Due to Coronavirus Shutdowns

Photo, posted May 7, 2020, courtesy of the MTA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Malaria With Gene-Drive Technology | Earth Wise

June 8, 2020 By EarthWise Leave a Comment

Malaria continues to be a major health hazard throughout the tropical and subtropical regions of the world. There were 228 million cases of malaria in 2018 and over 400,000 deaths.

Malaria is a mosquito-borne infectious disease spread by 40 of the world’s 3,500 mosquito species. So, efforts to control mosquito populations are the primary strategy to eradicate malaria.

A team led by Imperial College London has created a genetic modification that distorts the sex ratio of a population of Anopheles gambiae mosquitoes using “gene drive” technology. The modification works by using a DNA-cutting enzyme to destroy the X chromosome during the production of sperm, which leads to predominantly male offspring, since females require two X chromosomes. The modification is coupled to a gene drive to allow it to spread through a population in a very effective way. A gene drive is a genetic engineering technology that propagates a particular modification by assuring that a specific form of a gene (or allele) will be transmitted with far more than the natural 50% probability.

The result of this is that mosquitoes produce more male offspring, eventually leading to no females being born and a total collapse in the population. The mosquitoes studied are the main malaria vector in sub-Saharan Africa. The hope is that mosquitoes carrying a sex-distorter gene drive would be released in the future, spreading the male bias with local malaria-carrying populations and causing them to collapse. Only female mosquitoes bite and take blood meals. If the gene drive technology works in the field, it could be a game-changer in the fight to eliminate malaria.

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Malaria mosquitoes eliminated in lab by creating all-male populations

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

Earth Wise is a production of WAMC Northeast Public Radio.

Living In Extreme Heat | Earth Wise

June 3, 2020 By EarthWise Leave a Comment

Global climate change has already left observable effects on the planet. Glaciers have shrunk, trees are flowering sooner, plant and animal ranges have shifted, and so on. Many effects of climate change that scientists had predicted in the past are now occurring. The loss of sea ice, intensifying heat waves, and accelerating sea level rise are some examples.

According to a new study recently published in the journal Proceedings of the National Academy of Sciences, climate change is going to affect humans earlier, harder, and more widely than previously projected. The research team found that one billion people will be either displaced or endure insufferable heat for every one degree Celsius rise in global temperatures.

Under a worst case climate scenario, land that one third of the world’s population currently calls home will be as hot as the hottest parts of the Sahara desert within 50 years. Even under a more optimistic climate outlook, 1.2 billion people will still be exposed to temperatures outside the climate niche in which humans have thrived for at least 6,000 years.

The majority of the human population has always lived in regions where the average annual temperatures were between 43 degrees Fahrenheit and 82 degrees Fahrenheit. These are ideal temperatures for human health and for food production. But this temperature range is shrinking and shifting as a result of climate change.

The study’s authors predict there will be more change in the next 50 years than there has been in the past 6,000 years. They hope their findings will convince policymakers to accelerate their plans for emissions reductions and other climate mitigation strategies.

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Future of the human climate niche

One billion people will live in insufferable heat within 50 years – study

Photo, posted November 22, 2008, courtesy of Ronnie Finger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Too Many Bison | Earth Wise

May 8, 2020 By EarthWise Leave a Comment

The population of large herbivores in Yellowstone National Park has undergone many dramatic changes over the course of time. The numbers of both the iconic Rocky Mountain elk and bison have gone up and down as a result of human interactions.

Bison, of course, once were a dominant species from east of the Appalachians to west of the Rocky Mountains, with most of an estimated 30 million living on the Great Plains. As the west was settled, bison populations plummeted and by the late 1800s, they were nearly extinct.

When Yellowstone was established, there were exactly 22 bison in the park. By 1925, there were more than 750 in the park and culling of the herd in the park’s Lamar Valley was practiced for the next four decades.

The elimination of predators like grey wolves and cougars in the early 1900s caused both elk and bison populations to mushroom and both underwent culling. When culling was ended in 1968, there were 4,000 elk and 100 bison. Within 20 years, those numbers were 20,000 and 1,000. Reintroducing wolves and cougars reduced the elk population to about 5,000, but bison numbers have continued to grow, now reaching about 4,000.

While the long-term recovery of the Yellowstone bison herd is a major conservation success story, the fact is that bison are powerful ecosystem engineers. Large numbers of them disrupt species distribution across scrub steppe and grasslands because of what they eat, trample, and rub their horns and bodies on. They have a tremendous capacity to limit the structure and composition of ecosystems.

Park administrators have complicated management decisions to make to take into account the often wide range of ecological effects that abundant large herbivores can have on ecosystems.

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Bison in northern Yellowstone proving to be too much of a good thing

Photo, posted August 10, 2016, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar-Powered Desalination | Earth Wise

March 20, 2020 By EarthWise Leave a Comment

About 1% of the world’s population is dependent on desalinated water to meet daily needs, but water scarcity is a growing problem that experts believe will affect 14% of the world’s population within the next five years.

Desalination takes much more energy than, for example, transporting fresh water over large distances. In general, desalination costs are much higher than those associated with fresh water, but beyond costs, freshwater is simply not always available.

Researchers at MIT and Shanghai Jiao Tong University in China have developed a completely passive solar-powered desalination system that could provide more than 1.5 gallons of fresh drinking water per hour for every square meter of solar collecting area. Such a system could provide an efficient, low-cost water source for coastal areas that are off the grid.

The system uses multiple layers of flat solar evaporators and condensers topped with transparent aerogel insulation. The key to its efficiency is the way it uses each of its multiple stages to desalinate water. At each stage, heat released by the previous stage is harnessed instead of wasted. The proof-of-concept device, which was tested on an MIT building rooftop, produced more than twice as much water as the record amount produced by any previous passive solar-powered desalination system.

The researchers plan further experiments aimed at optimizing the choice of materials and configurations and to test the system under realistic conditions. The hope is to have a technology that can play a role in alleviating water scarcity in parts of the world where electricity is scarce, but seawater and sunlight are abundant.

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Simple, solar-powered water desalination

Photo courtesy of MIT/researchers.

Earth Wise is a production of WAMC Northeast Public Radio.

Conspicuous Consumption

February 6, 2020 By EarthWise 2 Comments

Human civilization consumes vast amounts of material. The Circle Economy think tank actually puts some numbers on it. According to their latest report, the amount of material consumed by humanity has passed 100 billion tons every year. So, on average, every person on Earth uses more than 13 tons of materials per year.

That number has quadrupled since 1970, which is far faster than the population, which has only doubled during that time. In the past two years alone, consumption has jumped by more than 8%. While this has been going on, the proportion being recycled has been falling.

Of the 100 billion tons of materials, half of the total is sand, clay, gravel, and cement used for building, along with other minerals used for fertilizer. Coal, oil and gas make up 15% and metal ores 10%. The final quarter are plants and trees used for food and fuel. About 40% of all materials are turned into housing. A third of the annual materials consumed remain in use, such as in buildings or vehicles. But 15% is emitted into the atmosphere as greenhouse gases and a third is treated as waste.

The global emergencies of climate change and disappearing wildlife have been driven by the unsustainable extraction of fossil fuels, metals, building materials, and trees. The authors of the report warn that if we continue to treat the world’s resources as limitless, we are heading for a global disaster.

The Circle Economy think tank promotes the idea of a circular economy in which renewable energy supports systems where waste and pollution are reduced to zero. Some nations are taking steps towards circular economies, while others are not. This is a problem we can’t allow to be unaddressed.

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World Consumes 100 Billion Tons of Materials Every Year, Report Finds

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

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The March Of The Penguins Toward Extinction

November 28, 2019 By EarthWise Leave a Comment

According to a new study from the Woods Hole Oceanographic Institution, the warming climate may render emperor penguins extinct by the end of this century. The study, which was part of an international collaboration between scientists, finds that emperor penguins will likely experience an 86% decline by 2100 if the global climate continues to warm at the current rate. At that point, it would be very unlikely for them to recover, according to the study’s lead author.

The research was funded by the National Science Foundation and recently published in the journal Global Change Biology.

The fate of emperor penguins is largely tied to the fate of sea ice. The penguins use sea ice as a place for breeding, feeding, and molting. They look for very specific conditions of sea ice – it must be locked in to the Antarctic shoreline but also close enough to open seawater to give them access to food. The study predicts that this sea ice will gradually disappear, depriving the birds of their habitat, food sources, and ability to raise their young.

The researchers combined two existing computer models to study three different climate change scenarios. If the average global temperature increases by only 1.5 degrees Celsius, the study found that only 5% of sea ice would be lost by 2100, resulting in a 19% drop in penguin colonies. If the planet warms by 2 degrees Celsius, the sea ice loss nearly triples and more than a third of penguin colonies disappear. The ‘business as usual’ scenario where the planet continues to warm at the current rate will ensure a near complete loss of emperor penguin colonies by 2100.

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Unless warming is slowed, emperor penguins will be marching towards extinction

Photo, posted January 15, 2011, courtesy of Eli Duke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Buses In Latin America

October 31, 2019 By EarthWise Leave a Comment

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

October 28, 2019 By EarthWise Leave a Comment

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.

Solar-Powered Desalination

October 4, 2019 By EarthWise Leave a Comment

Turning seawater into drinking water is an energy-intensive process and is therefore pretty expensive. Worldwide, one third of people don’t have reliable access to safe drinking water and they are the least able to afford expensive ways to get it. By 2025, half of the world’s population is expected to live in water-stressed areas.

At a newly-constructed facility in Kenya, a nonprofit company called GivePower has built a desalination system that runs on solar power. The system started operating in the coastal area of Kiunga in July 2018 and can create nearly 20,000 gallons of fresh drinking water each day – enough for 25,000 people.

GivePower started in 2013 as a nonprofit branch of SolarCity, the solar-panel company that ultimately merged with Tesla in 2016. However, GivePower spun off as a separate enterprise shortly before that.

GivePower mostly focuses on building solar-energy systems to provide electricity across the developing world.

Desalination technology is not new, but it is notoriously energy-intensive because it requires high-power pumps. The GivePower system is integrated with a solar microgrid that makes use of Tesla batteries to store energy for when the sun is not shining.

Local residents pay about a quarter of one cent for every quart of water from the system. The Kiunga community has faced ongoing drought and before the GivePower system was installed, was forced to drink from salt water wells, which present serious health risks.

The GivePower system cost $500,000 to build and is expected to generate $100,000 a year, to be eventually used to fund similar facilities in other places.

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A solar-powered system can turn salt water into fresh drinking water for 25,000 people per day. It could help address the world’s looming water crisis.

Photo courtesy of GivePower.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Energy Demand

August 7, 2019 By EarthWise Leave a Comment

Human beings are utterly dependent upon energy both for our well-being and for societal development. Our energy use is highly dependent upon climate since so much energy is expended either keeping us warm in winter or cool in summer. As the climate changes, it is important to understand how energy demand is likely to be affected.

A new study published in Nature Communications by researchers in Austria, Italy and the United States explored this topic. The study is a global analysis using temperature projections from 21 climate models, and population and economy projections for five socioeconomic scenarios. The purpose was to determine how energy demand would shift relative to today’s climate under modest and high-warming scenarios by the year 2050.

The findings indicate that, compared to scenarios in which energy demand is driven only by population and income growth, climate change will increase the global demand for energy by 11-27% by the year 2050 under a modest warming scenario. With vigorous climate warming, energy demand would increase by 25-58%. (Large areas of the tropics, as well as southern Europe, China, and the US are likely to experience the highest increases).

These findings are important because if energy use rises and leads to additional emissions of heat-trapping greenhouse gases, it will be increasingly difficult to mitigate future climate warming. Quantifying this risk provides even more incentive for reducing greenhouse gas emissions before these effects upon demand are realized and it becomes even more difficult to prevent further impacts.

Policymakers need to be aware that even moderate levels of climate change will lead to increases in energy demand that will make it increasingly difficult to minimize the harmful effects on their societies.

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More energy needed to cope with climate change

Photo, posted December 15, 2008, courtesy of Matt Hintsa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bad News For Penguins

June 21, 2019 By EarthWise Leave a Comment

The second-largest breeding colony of emperor penguins in Antarctica, located in the Waddell Sea, has experienced “catastrophic breeding failure” for the past three years. Nearly all of the colony’s chicks have failed to survive due to the breakup of sea ice, according to a new study published in the journal Antarctic Science.

The colony was once home to 14,000 to 25,000 breeding pairs, which represents as much as 9% of the global emperor penguin population. Emperor penguins are the tallest and heaviest of all living penguins, reaching up to 4 feet in height and weighing between 50 and 100 pounds. They are the only penguin species that breeds during the Antarctic winter and their lengthy treks to breeding colonies have been the subject of numerous films and television shows.

Sea ice at Halley Bay in Antarctica had been stable and reliable for nearly 60 years but stormy weather in 2016 driven by El Nino conditions, strong winds, and record low ice extent caused the ice on which penguin chicks gather to break up. This happened again in 2017 and 2018. By last year, just a few hundred adult pairs were present at the breeding site and almost no chicks survived the ice breakup.

Researchers say that they have never seen a breeding failure on a scale like this in 60 years of studying the colonies. On a more positive note, while the population of the Halley Bay site has collapsed, the Dawson-Lambton breeding area – located about 34 miles away – has actually seen significant growth over the past four years. While this is encouraging, the growth at Dawson-Lambton does not fully compensate for the losses at Halley Bay, which was once considered relatively safe from the impacts of climate change.

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