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Big Food and greenhouse gas emissions

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The global food system is responsible for as much as 40% of human-generated greenhouse gas emissions. The investor advocacy group Ceres has tracked whether the 50 largest North American food and agriculture companies have set targets to lower their emissions and whether doing so has actually resulted in lower emissions.

The emissions from food and agriculture companies are grouped into three so-called scopes.  Scope 1 are emissions from a company’s direct operations.  Scope 2 are emissions from its energy use.  Scope 3 are emissions from a company’s supply chain:  from the farmers who grow crops, raise cattle, and otherwise provide necessary items for a company’s final products.  In the food industry, the scope 3 category is responsible for about 90% of overall emissions.

Of the 50 food companies studied, 23 reduced their scope 1 and scope 2 emissions over the past 2 years, but only 12 reduced their scope 3 emissions.  Companies have more control over their scope 1 and scope 2 emissions. 

Reducing scope 3 emissions is more difficult.  And most companies haven’t set scope 3 reduction targets. 

The findings of the study suggest that reducing scope 3 emissions is especially difficult for companies whose supply chains are linked to carbon-intensive commodities, like meat, or crops linked to deforestation or land-use change, both of which result in increased emissions.

In March, the Securities and Exchange Commission finalized rules requiring companies to disclose their climate risk to regulators, increasing the visibility of the food industry emissions issue.

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North America’s Biggest Food Companies Are Struggling to Lower Their Greenhouse Gas Emissions

Photo, posted October 13, 2011, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why are bees making less honey?

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Scientists have been sounding the alarm on the global struggle of pollinators for a long time.  According to the United Nations, nearly 35% of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators.  Honey bee colonies in the United States have experienced annual population declines since 2006.  But in addition to there being fewer bees, the bees that remain are also making less honey.  In fact, honey yields in the United States have been declining since the 1990s. 

A new study by researchers from Penn State University has solved some of the mystery.  Using five decades of data across the United States, the research team analyzed the factors that could be affecting the number of flowers growing in different regions, which, in turn, affects the amount of honey produced by bees. 

In the study, which was recently published in the journal Environmental Research, the scientists found that climate conditions and soil productivity were two of the biggest factors in estimating honey yields.  States in both warm and cool regions produced higher honey yields when they had productive soils.  These two factors set a baseline production level of honey, while herbicide use, weather, and land use changes influenced how much honey was produced in a given year. 

The study’s findings  provide valuable insights that should help beekeepers, growers, and land managers better support honey bees.

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Why are bees making less honey? Study reveals clues in five decades of data

Photo, posted August 30, 2021, courtesy of Brandon O’Connor / NRCS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why was 2023 so hot?

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Five separate weather-tracking organizations have proclaimed 2023 as the hottest year on record. They all agreed that 2023 beat the previous record-holder – 2016 – by a wide margin.  Organizations that use a pre-industrial baseline of 1850-1900 found that 2023 was 1.45 to 1.48 degrees Celsius above the baseline.  But what caused 2023 – especially the second half of it – to be so hot?

Scientists believe that there were multiple factors that contributed to the record-breaking heat.

First and foremost is the long-term rise in greenhouse gases.  Over 100 years of burning fossil fuels along with major changes in land use (particularly deforestation) have led to a significant rise in the heat-trapping blanket of the gases in the atmosphere.

On top of this long-term trend, the return of the El Niño condition in the Pacific in May helped temperatures rise further.

At the same time, the tropical Pacific was not the only ocean that was hotter than normal.  The global sea surface temperature set new records in 2023 and there were multiple marine heat waves.  Heat trapped by the atmosphere is absorbed by the oceans, raising their temperatures.

Another factor is the quantity of aerosols in the atmosphere.  Many of these aerosols actually cool the atmosphere by reflecting the sun’s light back into space.  Society’s efforts to reduce air pollution and improve air quality have led to decreasing levels of aerosols.

2024 started with some seriously cold weather in some places but predictions are that this year will be roughly as warm as 2023 and possibly warmer given that the dynamics driving last year’s weather are all still in place.

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Five Factors to Explain the Record Heat in 2023

Photo, posted February 22, 2016, courtesy of Jasmin Toubi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record high emissions

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The world is adding solar and wind power to the grid.   We are driving more and more electric cars.  Countries are pledging to cut back fossil fuel use.  There are highly visible international conferences on the climate crisis.   But despite all of these things, global carbon emissions from fossil fuels have risen once again in 2023, reaching all-time record high levels of more than 40 billion tons, about 1.1% more than the previous year.

In some places, including Europe and the U.S., fossil fuel CO2 emissions are falling, but globally, they are still rising.  Emissions continued to increase in India and China.  Global action to cut fossil fuel use is not happening fast enough to prevent the increasingly dangerous effects of climate change.

Global CO2 emissions include both the contributions of fossil fuel use and the effects of land use change.  Adding the two together, in 2023 the total was about 45 billion tons, basically unchanged from last year. 

Adding insult to injury are the emissions from fires.  The extreme wildfire seasons in Canada, Australia, and other places have contributed CO2 emissions much larger than historical averages.

About half of all the carbon dioxide emitted on Earth is absorbed by carbon sinks on land and the oceans.  The other half remains in the atmosphere, where levels are now averaging 419 parts per million, 51% above pre-industrial levels.

Current efforts are simply not profound enough or widespread enough to put global emissions on a downward trajectory.  Some climate policies in some places are proving effective, but much more needs to be done.

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Fossil CO2 emissions at record high in 2023

Photo, posted December 18, 2013, courtesy of Steve Nelson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Coffee, cocoa, and pollinators

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Multiple forces have been at play that have been detrimental to pollinators including climate change, land use change, pesticide use, and more.  There have been substantial declines in both the abundance and diversity of insect pollinators.  There is increasing public awareness of this issue, but it hasn’t really risen all that high among many people’s concerns.

A new study by University College London looked at the effects of the global decline in pollinators on thousands of crop-growing sites around the world involving thousands of insect pollinator species.

About 75% of all crops grown depend on pollinators to some degree.  The UCL research created a model that looks at which pollination dependent crops are most threatened over the next 30 years in order to provide a warning to both the agricultural and conservation communities.

The research indicates that the tropics are likely to be most at risk with regard to reduced crop production caused by pollinator losses.  This is mostly due to the interaction of climate change and land use.  The risks are highest in sub-Saharan Africa, northern South America, and southeast Asia.

These areas are where the world gets most of its coffee and cocoa, two crops that are near and dear to most of us.  These crops, as well as others such as mangoes, play vital roles in both local economies and global trade and reducing them could lead to increased income insecurity for millions of small-scale farmers in these tropical regions.

If pollinator loss isn’t high up on your list of global concerns, perhaps you should think about it next time you have a cup of coffee or enjoy some chocolate.

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Coffee and cocoa plants at risk from pollinator loss

Photo, posted May 23, 2013, courtesy of McKay Savage via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Climate Impact Of Diets | Earth Wise

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The food system is responsible for 70% of the world’s freshwater use and almost 80% of freshwater pollution.  About three-quarters of the ice-free land area of the planet has been affected by human use, primarily for agriculture.  Land-use change such as deforestation is a major source of biodiversity loss.  What we choose to eat has a major effect on how the food system impacts the environment.

A comprehensive study by researchers at several UK universities has found that a plant-based diet yields one-fourth as much greenhouse gases as a diet rich in meat.  Vegan diets produce 75% less heat-trapping gas, generate 75% less water pollution, and use 75% less land than meat-rich diets.

Just going to a low-meat diet cuts the environmental cost of a high-meat diet in half.  Pescatarian diets perform better than low-meat diets, and vegetarian diets do even a little better than that.

There are a variety of reasons why many people won’t, can’t, or even shouldn’t become vegans.  What should be learned from this study is that our dietary choices have a major environmental impact.  So, taking actions like cutting down the amount of meat and dairy – which most people can do with relative ease – can be valuable.

There are many choices with respect to where we live, how we get from place to place, where we get our food, and, yes, what food we eat, that impact the environment.  We are not all going to do the best possible thing in all these cases, but if we each make some choices that at least help, it can make a big difference.

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Vegan Diets Have One-Fourth the Climate Impact of Meat-Heavy Diets, Study Finds

Photo, posted November 5, 2017, courtesy of Stephanie Kraus via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

North American Birds And Climate Change | Earth Wise

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Most plants and animals live in areas with specific climate conditions, such as rainfall patterns and temperature, that enable them to thrive. Any change in the climate of an area can affect the plants and animals living there, which in turn can impact the composition of the entire ecosystem.   

As such, the changing climate poses many challenges to plants and animals.  For example, appropriate climatic conditions for many species are changing.  As a result, some may even disappear altogether.  These problems can be compounded when the climate is changing in tandem with other human-caused stressors, such as land use change.

When there is increasing divergence between suitable climatic conditions for a particular species and its abundance and distribution through time, this is known as climate decoupling.

According to a new study recently published in the journal Nature Ecology & Evolution, some species of North American birds have not fully adjusted their distributions in response to climate change.  The areas where these birds live have become more decoupled from their optimal climate conditions.  Climate decoupling as a result of ongoing climate change could lead to additional stressors on many bird species and exacerbate bird population declines.

In the study, the research team analyzed data on bird population changes through time from the North American Bird Survey.  They found that at least 30 out of 114 species (or 26%) of North American birds have become less well adjusted to their climate over the last 30 years. This means that their distributions and abundances were increasingly decoupled from climate over time.

The researchers also found that the overall trend of climate decoupling shows no signs of slowing down. 

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North American birds not fully adjusting to changing climate

Photo, posted July 16, 2016, courtesy of Kelly Azar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Forest Loss | Earth Wise

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India is one of the most biodiverse countries in the world.  An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species. 

India is also among the top ten countries in the world in terms of total forest coverage.  According to Indian government data, the total forest and tree cover in India is 312,000 square miles, which is 24.62% of the geographical area of the country.

However, forest loss in India has been a problem for many decades driven largely (researchers thought) by land use change.  But it turns out that climate change may also have been contributing to forest loss, and its impact is projected to become an even bigger problem in the coming years. 

In the first ever national-scale study of the relationship between forest loss and rainfall and temperature trends in India, researchers from the University of Reading in the U.K. found that climate change may have contributed to large declines in forest since the turn of the century.

The study, which was recently published in the journal Global Change Biology, found far greater forest losses were observed where and when the climate was changing most rapidly.  Decreases in rainfall had the strongest impact on forest loss. 

These findings exacerbate concerns about the already-worrying levels of deforestation in the country, and contradict official reports that have shown relatively small decreases in forest coverage in recent years. 

The research team warns that rapid changes to the climate in some regions will require targeted preservation action to reduce the risk to biodiversity in India. 

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Indian forest loss ‘worse than feared’ due to climate change

Photo, posted January 20, 2013, courtesy of Dicky Broadhurst / Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Food And Greenhouse Gas Emissions | Earth Wise

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According to a study published in the journal Nature Food, the world’s food systems are responsible for more than one third of global greenhouse gas emissions caused by human activities. 

‘Eat Local’ is often recommended as a way to minimize the carbon footprint of our diet.  But from a climate impact perspective, eating local only has a significant impact if transportation is responsible for a large portion of a food’s final carbon footprint.  And in many cases, greenhouse gas emissions related to transportation make up only a small portion of the emissions from food and what we eat is far more important. 

There are massive differences in the greenhouse gas emissions of various foods. 

For example, producing one pound of beef generates 60 pounds of greenhouse gas emissions.  This is more than double the next closest food (lamb), and more than 60 times greater than some plant crops like corn and cassava. 

For most foods – especially the largest emitters – greenhouse gas emissions from land use change combined with the emissions from processes at the farm stage account for more than 80% of the environmental footprint.  Meanwhile, transportation accounts for less than 10%, and its contribution for the largest emitters is even smaller.  For example, transportation accounts for 0.5% of emissions from beef production.

Eating beef or lamb has many times the carbon footprint of most other foods.  It matters very little in terms of emissions whether it was grown locally or shipped from another part of the world.  It’s not the location that makes the carbon footprint of our dinner large.  It’s what is on our plate that matters.

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Food systems account for over one-third of global greenhouse gas emissions

You want to reduce the carbon footprint of your food?

Photo, posted November 7, 2018, courtesy of Preston Keres / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How To Bend The Curve On Biodiversity Loss | Earth Wise

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Biodiversity has been declining at an alarming rate in recent years as a result of human activities, including land use changes, pollution, and climate change.  According to a 2019 UN report, one million species – out of an estimated eight million – are threatened with extinction.  Many scientists warn we are in the middle of the sixth mass extinction event in Earth’s history.  Previous mass extinction events wiped out up to 95% of all species and took ecosystems millions of years to recover. 

Fortunately, new research indicates that it might not be too late to bend the curve on biodiversity loss.  According to the report, which was recently published in the journal Nature, more ambitious conservation measures are needed in order to  preserve biodiversity.  In addition, more efficient food production and healthier and less wasteful consumption and trade are needed to bend the curve. 

If these measures are undertaken with unprecedented ambition and coordination, the research team says the efforts will provide an opportunity to reverse biodiversity loss by 2050.

But even under the best case scenario, ongoing land conversion will lead to further biodiversity losses before the curve starts to bend.  In fact, at least one third of projected losses in the coming years are unlikely to be avoided under any scenario.  Biodiversity losses were projected to be highest in the regions richest in biodiversity, including South Asia, Southeast Asia, Sub-Saharan Africa, the Caribbean, and Latin America. 

The study, which was led by the International Institute for Applied Systems Analysis in Austria, makes it clear that urgent action is needed this decade in order to have any chance of bending the curve. 

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Curbing land clearing for food production is vital to reverse biodiversity declines

Photo, posted November 1, 2017, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Land Use Change And Flooding | Earth Wise

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Land use change refers to the conversion of a piece of land’s use by humans from one purpose to another. Land use change is commonly associated with biodiversity loss and increased greenhouse gas emissions.  But how does land use change impact water cycles? 

According to researchers from the University of Göttingen in Germany, IPB University, and BMKG (both in Indonesia), the expansion of monocultures, such as rubber and oil palm plantations, leads to more frequent and more severe flooding.  The researchers explain the increase in flooding “with a complex interplay of ecohydrological and social processes, including soil degradation in monocultures, the expansion of oil palm plantations into wetlands, and the construction of flood protection dams.” 

For the study, which was recently published in the journal Ecology & Society, the research team interviewed nearly 100 Indonesian farmers, villagers, and decision-makers in Sumatra.  The team supplemented its research with data on precipitation, river and groundwater levels, soil properties, and regional mapping. 

During large-scale land use change – like plantation expansions – newly-compacted soil causes rainwater to runoff as opposed to being absorbed.  As more plantations are established in floodplains, the owners try to control flooding on their land by building barriers.  But these dams often lead to increased flooding on neighboring lands.  This understandably triggers social tensions between other farmers and plantation owners.     

In order to reduce the negative impact of land use change on the water cycle, the research team suggests soil protection and improved planning – especially in floodplains – would be a good place to start.  

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Land use change leads to increased flooding in Indonesia

Photo, posted October 8, 2018, courtesy of Artem Beliaikin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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