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2023: A year of extreme climate

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There have already been all sorts of extreme weather this year in many parts of the world and undoubtedly there will be more to talk about in the coming months.  But the American Meteorological Society has recently published its State of the Climate report for 2023 and it was a year for the record books.

In 2023, the Earth’s layers of heat-reflecting clouds had the lowest extent ever measured.  That means that skies were clearer around the world than on average, a situation that amplifies the warming of the planet.  Since 1980, clouds have decreased by more than half a percent per decade. 

The most dramatic climate effect last year occurred in the world’s oceans.  About 94% of all ocean surfaces experienced a marine heatwave during the year.  The global average annual sea surface temperature anomaly was 0.13 degrees Celsius above the previous record set in 2016.  This is a huge variation for the ocean.  Ocean heatwave conditions stayed in place for at least 10 months in 2023 in vast reaches of the world’s oceans.  Ocean heat was so remarkable that climate scientists are now using the term “super-marine heatwaves” to describe what is going on. 

There were many other ways in which 2023 experienced weather extremes.  July experienced a record-high 7.9% of the world’s land areas in severe drought conditions.  During the year, most of the world experienced much warmer-than-average conditions, especially in the higher northern latitudes.  These unprecedented changes to the climate are unlikely to be one-time occurrences; 2024 is likely to be another one for the record books.  

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New Federal Report Details More of 2023’s Extreme Climate Conditions

Photo, posted May 27, 2021, courtesy of Wendy Cover/NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Species and climate change

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Temperature extremes on Earth currently range from a low of -129°F to a high of 134°F.  But these climatic limits have changed throughout history.  In fact, during the last interglacial period 130,000 years ago, temperatures were warmer, resembling what we are projected to experience at the end of this century.

Species that evolved during such periods may possess pre-adaptations that could help them tolerate upcoming changes to the climate.  This factor is often overlooked by traditional statistical models predicting species’ responses to climate change.

But a new model, developed by researchers from Ifremer in France and Lausanne University in Switzerland, has taken this oversight into account, and reassessed the proportion of terrestrial and marine species threatened with extinction by climate change. 

In the study, which was recently published in the journal Nature Ecology and Evolution, the research team applied its model to nearly 25,000 terrestrial and marine species from around the world.  The researchers discovered that 49% of these species live in climate niches near the current climatic limits, and 86% could potentially extend beyond these limits. 

The most surprising result concerns tropical regions. While forecasts from traditional models estimate that the diversity of terrestrial species in tropical areas could decrease by 54% between now and 2041-2060, the new model predicts a more moderate decline of 39%.

The findings confirm the importance of taking urgent measures to mitigate climate change and its impact on biodiversity.

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Some species may better tolerate climate change than expected

Photo, posted October 23, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Skiing and climate change

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According to the National Oceanic and Atmospheric Administration, anthropogenic climate change resulting in higher average temperatures has caused a global decline in snowfall.  Less snow threatens to reinforce global warming, and to disrupt food, water, and livelihoods for billions of people.  

According to a new study recently published in the journal PLOS ONE, annual snow cover days in all major skiing regions are projected to decrease dramatically as a result of climate change.  In the study, the research team from the University of Bayreuth in Germany examined the impact of climate change on annual natural snow cover in seven major skiing regions.  Using the public climate database CHELSA, the researchers predicted annual snow cover days for each ski area for 2011-2040, 2041-2070, and 2071-2100 under low, high, and very high carbon emissions scenarios.

Under the high emissions scenario, 13% of ski areas are predicted to lose all natural snow cover by 2071-2100 relative to their historic baselines.  By 2071-2100, average annual snow cover days were predicted to decline by 78% in the Australian Alps, 51% in the Southern Alps, 50% in the Japanese Alps, 43% in the Andes, 42% in the European Alps, 37% in the Appalachians, and 23% in the the Rocky Mountains – all declines relative to their historic baselines.

The future losses of natural snow cover in ski areas around the world will be significant if global emissions continue unchecked.

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The future is likely less skiable, thanks to climate change

New maps show where snowfall is disappearing

Photo, posted April 14, 2006, courtesy of Kallu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy efficient cows

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Livestock production – primarily cows – produce nearly 15% of global greenhouse gas emissions, mostly in the form of methane emitted by burping caused by the way they process food.  A single cow produces roughly 200 pounds of methane gas per year and there are 1.5 billion heads of cattle in the world.

Researchers at Penn State University have found that supplementing the feed of high-producing dairy cows with the botanical extract capsicum oleoresin – a substance obtained from chili peppers – or a combination of that extract and clove oil resulted in the animals using feed energy more efficiently. 

Adding these substances – which are commonly called essential oils – to the cattle’s feed results in improved efficiency of energy utilization.  It is known that botanicals have the potential to modify fermentation in the cow’s largest stomach – called the rumen.

There have been previous studies for many years adding substances to dairy cow feed – such as seaweed, garlic, and oregano – in an effort to improve milk production and reduce environmental emissions from dairy farms.

The Penn State study was actually not specifically aimed at methane reduction but rather to better use the available energy from the feed to gain body weight.  However, the researchers found that the yield and intensity of methane from the cows in the study were decreased by 11% by the combination of capsicum oleoresin and clove oil.

Botanicals have shown a wide range of anti-microbial properties against bacteria, protozoa, and fungi, as well as being potential rumen modifiers in cattle.  The new study represents an interesting approach to improve the metabolism of dairy cows.

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Dairy cows fed botanicals-supplemented diets use energy more efficiently

Photo, posted April 9, 2012, courtesy of Aimee Brown / OSU via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking African glaciers

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We don’t usually associate Africa with glaciers, but the continent has had glaciers on its highest peaks for the past 10,000 to 15,000 years.  Africa’s glaciers are found in three regions:  the Rwenzori Mountains along the border between Uganda and the Democratic Republic of the Congo, Mount Kilimanjaro, and Mount Kenya.  At the turn of the 20th century, there were 43 glaciers scattered across 6 peaks within the Rwenzori Mountains.  In the intervening years, things have greatly changed.

 Since the early 20th century, Africa’s glaciers have shrunk by 90%.  Because all these glaciers are close to the equator, they are especially vulnerable to warming.  According to a new study published in the journal Environmental Research: Climate, in the last two decades, Africa’s glaciers have lost roughly half their area.

This rapid decrease is alarming to climate scientists because they represent a clear indicator of the impact of climate change.  A major factor in the decline of the glaciers is the reduction in cloud cover over the mountains.  Sunshine is melting glaciers and turning ice directly into water vapor even when temperatures are below freezing.  Reductions in snowfall at the same time means that the melting glaciers are not being replenished.

Scientists believe that the tropical glaciers of Africa may all but disappear over the next 25 years.

Roughly three-quarters of the Earth’s freshwater is stored in the world’s more than 200,000 glaciers.  According to scientists, if the world reaches but maintains 1.5 degrees of warming, half of the world’s glaciers could be gone by the end of this century.  If the world continues to warm as it has been without slowing down, more than 80% of the glaciers will disappear.

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Africa’s Tropical Glaciers Have Shrunk by 90 Percent, Research Shows

Photo, posted February 26, 2022, courtesy of Ray in Manila via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewables’ Growing Share | Earth Wise

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Not long ago, many states across the country were setting goals to obtain 20% of their electricity from renewable sources. For a few states, like New York and Washington, ample amounts of hydropower made 20% an easy target.  But for many others, 20% seemed like a very ambitious objective.

Things have certainly changed.  According to the latest monthly Short Term Energy Outlook, a report from the federal government, the combination of wind, solar, and other renewable sources will exceed one-quarter of the country’s generation by 2024.

Renewables are already at 24% of U.S. electricity generation and are expected to rise to 26% by next year.  Coal, which used to be the largest source of electricity, will continue to drop from its current 18% to 17% by next year.  Overall, renewables passed coal for the first full year in 2020.  Coal staged a bit of a comeback in 2021, but has once again resumed its decline.  Many coal-fired power plants continue to close, and there are not new ones being built because of diminishing economic benefits as well as concerns about emissions.

The largest source of electricity generation continues to be natural gas at 38%, but that number is also expected to slowly decrease over time. The growth in renewable energy is coming from wind and solar power.  Two-thirds of that growth is from solar and one-third is from wind. 

Together, wind and solar power will add up to 18% of the country’s electricity supply.  The government still tracks them lumped together as renewables, but both are so large and growing so quickly that the Energy Information Agency is likely to soon start tracking them as separate categories.

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Renewables Projected to Soon Be One-Fourth of US Electricity Generation. Really Soon

Photo, posted April 18, 2011, courtesy of Allan Der via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Drought And U.S. Hydropower | Earth Wise

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The ongoing severe drought in the western U.S. has led to low water levels in the rivers and reservoirs that feed hydroelectric power systems.  The Energy Information Administration is projecting a 13.9% decrease in hydroelectric generation this year compared to 2020.

Water levels in Lake Powell have fallen so low that it may not be possible to operate the power plant at Glen Canyon Dam starting as soon as 2022.  California officials took the Edward Hyatt hydroelectric plant offline in August because of low water levels on Lake Oroville.   Washington, the state with the most hydroelectric power generation, has seen an 11% drop in electricity generated to date this year as compared to last year.  That state is actually doing better than others in the West, such as California, where hydro generation is down 38%.

Hydropower accounts for over 7% of the electricity generated in the United States.  Five states – Washington, Idaho, Vermont, Oregon, and South Dakota – generate at least half of their electricity from hydroelectric dams.

The current decrease in hydropower is alarming, but it is not unprecedented.  The more significant question is whether the drop in generation this year is a sign that this power source is declining and becoming less reliable.   According to some scientists, the West is in a “megadrought” that could last for decades.

The greater concern is whether the bad years are likely to become more common because of climate change.  Climate projections agree that temperatures will continue to rise, but what will happen to precipitation levels in specific places is much less certain.  That is what will determine what the future holds for hydroelectric power.

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Inside Clean Energy: Drought is Causing U.S. Hydropower to Have a Rough Year. Is This a Sign of a Long-Term Shift?

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Extreme Wildfire Seasons | Earth Wise

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According to a new study led by researchers at Stanford University, autumn in California feels more like summer now as a result of climate change, and this hotter and drier weather increases the risk of longer and more dangerous wildfire seasons.

The research team, whose work was recently published in the journal Environmental Research Letters, found that the frequency of extreme fire weather conditions in the fall in California has doubled since the early 1980s.  Average temperatures during the season have increased by more than 2 degrees Fahrenheit, and rainfall has fallen by approximately 30%.  The most pronounced warming has occurred in the late summer and early fall.  That finding means that tinder-dry conditions coincide with the strong “Diablo” and “Santa Ana” winds that are typical in California at this time of year.     

In recent years, these conditions have fed large and fast-moving wildfires across California.  The state’s two largest wildfires, two most destructive wildfires, and the most deadly wildfire all occurred during 2017 and 2018, resulting in more than 150 deaths and $50 billion in damage.

Because summertime has typically been peak fire season, the recent spate of autumn fires is putting a strain on firefighting resources and funding.  The ongoing COVID-19 pandemic could further strain emergency resources.  Since fire-prone regions have historically shared  wildfire-fighting resources throughout the year, the consequences of California’s extended wildfire season could have a global impact.  (For example, California’s recent autumn wildfires have coincided with the beginning of wildfires in Australia). 

The researchers highlight some opportunities to manage the intensifying wildfire risk in California, including limiting the trajectory of global warming in keeping with the targets identified in the United Nations’ Paris agreement.

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Researchers forecast longer, more extreme wildfire seasons

Photo, posted September 12, 2019, courtesy of the California National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Agrivoltaics

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A new study by Oregon State University has found that the most productive places on Earth for solar power are farmlands.   In fact, if less than 1% of agricultural land was converted to solar panels, it would be sufficient to fulfill global electricity demand.

The concept of co-developing the same area of land for both solar photovoltaic power and conventional agriculture is known as agrivoltaics.

The synergy between agriculture and solar power is not surprising.   People have been growing crops around the planet for at least 8,000 years and, long ago, farmers found the best places to grow them which turn out to also the best places to harvest solar energy.  The needs for solar panels are pretty similar to those of food crops.  The efficiency of the panels decreases if they get too hot.  Barren land is hotter than cropland, so the productivity of solar panels is less in such places.

The Oregon State Study analyzed power production data collected by Tesla, which had installed five large grid-tied, ground-mounted solar electric arrays owned by Oregon State.  The researchers monitored air temperature, relative humidity, wind speed, wind direction, soil moisture, and incoming solar energy.  With the data, they developed a model for the best conditions for solar panel productivity and they coincide with excellent conditions for agriculture.  Solar panels are kind of like people with regard to the weather:  they are happier when it is cool and breezy and dry.

Previously-published research shows that solar panels actually increase crop yields on pasture or agricultural fields.

These new results have implications for the current practice of constructing large solar arrays in deserts.  Agricultural lands may be a much better option for both solar production and crop production.

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Installing solar panels on agricultural lands maximizes their efficiency, new study shows

Photo, posted April 20, 2011, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling U.S. Carbon Emissions

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Reducing carbon emissions is a goal embraced by nearly every country in the world, but actually accomplishing it isn’t easy. It is true that renewable energy sources are playing a growing role in energy systems, but counterbalancing that trend is growing energy demand, especially in developing countries.

Here in the US, energy-related CO2 emissions actually went up nearly 3% in 2018 compared with 2017.  But the US Energy Information Administration is now forecasting a 2% drop in emissions this year.

The main reason energy-related emissions are headed lower at this point is coal-fired power plant retirements.  More than 90% of the coal used in the US goes toward electric power and utilities are increasingly turning away from coal.

The rapid shift away from coal has mostly been due to the increasing use of natural gas.  Natural gas is not actually a clean and green fuel, but it is definitely less carbon-intensive than coal.  Overall, the total installed capacity of renewable sources – hydropower, wind, solar, geothermal, and biomass – has now actually surpassed the capacity of coal plants.  Given that renewables have in many places become the cheapest power option, there is little chance that coal has much of a future, despite efforts by the current administration.

The electric power sector is gradually moving away from all carbon-emitting sources – a trend that is being reinforced by legislation in many states.  The real CO2 emissions leader is petroleum, which accounts for nearly half of the total.  We have a long way to go to reduce emissions from the use of petroleum.  There are over 250 million cars and trucks on US roads and only a little over a million of them don’t burn fossil fuels.

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US energy-related CO2 emissions expected to fall this year, almost solely due to a drop in coal use

Photo, posted November 6, 2017, courtesy of Cindy Shebley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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