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Bad news for birds

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The 2025 U.S. State of the Birds report was released recently.   The report is produced by a coalition of leading science and conservation organizations.  The bottom line is that there have been continued widespread declines in American bird populations across all mainland and marine habitats. 

More than one-third of U.S. bird species are of high or moderate conservation concern.  Among these, 112 are tipping point species that have lost more than 50% of their populations over the last 50 years. 

Protecting bird species is not just about biodiversity and stewardship of nature.  Wild birds have surprisingly large economic impact.  Nearly 100 million Americans are engaged in birding activities which contribute substantially to local and state economies.  The 2022 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation estimated that the total economic output related to bird watching activities was an amazing $279 billion and birding-related activities support 1.4 million jobs.  Bird watching and other encounters with nature are beneficial for human well-being, including reducing stress, anxiety, and depressive symptoms.

The rapid declines in birds are related to habitat loss, environmental degradation, and extreme weather events.  Moreover, if conditions are not healthy for birds, they are unlikely to be healthy for people as well.  Fortunately, many actions that are good for birds are good for us, so conservation efforts going forward are important.

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State of America’s birds: Population declines continue

Photo, posted October 30, 2018, courtesy of Shenandoah National Park via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Thawing permafrost:  Is it a ticking timebomb?

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Permafrost covers about a quarter of the landmass in the Northern Hemisphere.  It stores vast quantities of organic carbon in the form of dead plant matter.  As long as it stays frozen, it is no threat to the climate.  But as it thaws, microorganisms start breaking down that plant matter and large amounts of carbon are released into the atmosphere in the form of carbon dioxide and methane.

This process has often been described as a ticking timebomb for the climate.  The theory is that once global warming reaches a certain level, the process will become self-amplifying setting off a catastrophic amount of warming.  If that level was reached, it would be a tipping point in the changing climate.

An international research team from the Alfred Wegener Institute in Germany has extensively researched this hypothesis.  Their conclusion is that within the permafrost, there are multiple geological, hydrological, and physical processes that are self-amplifying and, in some cases, irreversible.  However, these processes act only locally or regionally.  There is no evidence that some particular threshold in global warming could affect all permafrost and accelerate its thawing on a global level.

This research does not mean that Arctic permafrost is nothing to worry about.  In fact, there are ways in which it is more worrisome.  Because the permafrost is very heterogenous – meaning it is very different in different places – there will be numerous small, local tipping points that will be exceeded at different times and at different levels of warming.  All of this will proceed in step with global warming, contributing to the overall worsening situation.  There is no warming level below which permafrost thawing is not a problem.

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Thawing permafrost: Not a climate tipping element, but nevertheless far-reaching impacts

Photo, posted January 24, 2014, courtesy of Brandt Meixell / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Is the Amazon rainforest nearing a tipping point?

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The Amazon rainforest is the largest rainforest in the world, covering more than 2.5 million square miles.  More than three million species live in the rainforest, which constitutes approximately 10% of the world’s known biodiversity.  The Amazon rainforest’s biodiversity is so rich that scientists are still discovering new species all the time. 

The Amazon rainforest absorbs huge amounts of carbon dioxide from Earth’s atmosphere, making it a key part of mitigating climate change.  But the amount of carbon dioxide absorbed by the Amazon rainforest today is 30% less than it was in the 1990s. 

Deforestation of the Amazon rainforest remains a major problem. Cattle ranching is the leading cause of deforestation, but industrial activities, such as the mining of oil and gas, copper, iron, and gold, are also to blame.

According to a new study recently published in the journal Nature, global warming may be interacting with regional rainfall and deforestation to accelerate forest loss in the Amazon.  In fact, it may be pushing the rainforest towards a partial or total collapse. 

The study, which was led by researchers from Federal University of Santa Catarina in Brazil and the University of Birmingham in the U.K., has identified the potential thresholds of these stressors, and highlighted how their combined effects could produce a tipping point for the Amazon rainforest. 

The findings are important because the Amazon rainforest plays a vital role in the global climate system.  By identifying the most important stressors on the rainforest environment, the researchers hope they can develop a plan to keep the Amazon rainforest resilient.

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Is the Amazon forest approaching a tipping point?

Photo, posted July 2, 2017, courtesy of Anna & Michal via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Who wins: Wind or solar?

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A new study by the University of Exeter in the UK suggests that the world may have crossed a tipping point that will inevitably make solar power our main source of energy.  This data-driven model of technology seems to fly in the face of the current situation in which wind power contributes considerably more generation than solar power – by a factor of 3 in the U.S. and nearly double worldwide.

Wind and solar power both have advantages and disadvantages.  Solar power is quiet, requires little maintenance, and presents little danger to wildlife.  It is also practical for individual homes.  Residential wind power is not really a viable option for most people in most places.  But on the other hand, wind energy can produce more power than solar, can work both day and night, and can be located offshore far away from people.  On land, both wind and solar power take up lots of space and compete with other land use needs as well as countering people’s aesthetic preferences.

Both technologies continue to get cheaper over time, although solar has especially seen significant cost reductions.  The cost of solar power, which is already the cheapest form of electricity production, is estimated to fall to as low as $20 per megawatt hour over time from the current level of $40 per megawatt hour.

Wind and solar energy are on track to account for more than a third of the world’s electricity by 2030, according to the Rocky Mountain Institute.  Despite the predictions of various studies and the ambitions of specific technologies, it seems likely that wind and solar power will both play an expanding role in our energy systems for a long time to come.

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World may have crossed solar power ‘tipping point’

Photo, posted November 22, 2008, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Positive Tipping Points And Climate | Earth Wise

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A tipping point is a moment when a small change triggers a large and possibly irreversible response.

There has been much discussion of various tipping points that could accelerate climate change in catastrophic ways.  A recent paper from researchers at the University of Exeter in the UK discusses a couple of tipping points that could accelerate positive progress on mitigating climate change.

Electric vehicles account for only 2-3% of new car sales globally. In Norway, this figure is more than 50%, mostly thanks to policies that make electric cars the same price to buy as conventional cars.   According to the Exeter study, when EVs cost the same to manufacture as conventional cars, it will be a global tipping point.  China, the EU, and California together are responsible for half of the world’s car sales and each of these has targets to rapidly decarbonize their economies and policies in place to speed the transition to electric vehicles. 

Decarbonizing electric power is the other potential positive tipping point.  In Europe, carbon taxes on top of increasing renewable energy generation have tipped coal into unprofitability as they have led to the irreversible destruction of coal plants.  Globally, renewables are already generating electricity cheaper than fossil fuels in many countries.  Decarbonizing global power generation would in turn help accelerate decarbonization of large parts of transportation, heating and cooling, and industry.

These potential positive tipping points are by no means inevitable.  Appropriate policies are needed to overcome various barriers to the clean energy transition.  But major changes in transportation and electric power would have a tremendous impact on the global effort to combat climate change.

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Positive ‘tipping points’ offer hope for climate

Photo, posted July 14, 2020, courtesy of Jim Champion via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Arctic Methane Starting To Release | Earth Wise

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An international team of researchers has found evidence that frozen methane deposits in the Arctic Ocean have started to be released over a large area of the continental slope off the East Siberian coast.  High levels of methane have been detected down to a depth of 1,100 feet in the Laptev Sea near Russia.

The slope sediments in the Arctic contain huge quantities of methane and other gases, known as hydrates.  Methane has a warming effect 80 times stronger than carbon dioxide over a 20-year period.  The US Geological Survey has identified Arctic hydrate destabilization as one of the four most serious scenarios for abrupt climate change.

The research team aboard a Russian ship said that most of the bubbles they observed coming up from the sea bottom were dissolving in the water, but that methane levels at the surface were four to eight times what would normally be expected.

Frozen methane deposits have been called the “sleeping giants of the carbon cycle.”  If these deposit releases were to reach a high enough level, it would be a tipping point that could greatly increase the speed of global warming.  With Arctic temperatures now rising more than twice as fast as the global average, the likelihood of a significant release of the frozen methane grows greater all the time.

Temperatures in Siberia were 9 degrees Fahrenheit higher than average from January to June this year.  Last winter’s sea ice melted unusually early.  This winter’s freeze has yet to begin, which is already a later start than any time on record.

These new discharges of methane are larger than anything found before and are a very worrisome occurrence.

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Arctic methane deposits ‘starting to release’, scientists say

Photo, posted September 26, 2014, courtesy of the Office of Naval Research via Flickr. Photo credit: U.S. Navy photo by John F. Williams/Released.

Earth Wise is a production of WAMC Northeast Public Radio.

Greenland Glaciers Past The Point Of No Return | Earth Wise

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Forty years of satellite data from Greenland shows that the glaciers on the island have shrunk so much that even if global warming came to an abrupt halt, the Greenland ice sheet would continue to shrink.

This conclusion was published in the journal Communications Earth and Environment by researchers at Ohio State University.  According to their study, Greenland’s glaciers have passed a tipping point where the snowfall that replenishes the ice sheet each year can no longer keep up with the ice that is flowing into the ocean from the glaciers.

The study analyzed monthly satellite data from more than 200 large glaciers that drain into the ocean around Greenland.  It looked at how much ice breaks off into icebergs or melts from the glaciers into the ocean as well as the amount of snowfall each year that replenishes the glaciers.

Throughout the 1980s and 90s, these two processes were mostly in balance, keeping the ice sheet intact.  But the amount of ice being lost each year started to increase steadily around the year 2000 while there was no increase in snowfall.   Both processes fluctuate from year to year, but the baseline for ice loss has steadily risen.  Before 2000, the Greenland ice sheet had about the same chance of gaining or losing mass each year.  At this point, the ice sheet is likely to gain mass in only one out of every 100 years.

Large glaciers in Greenland have retreated about 2 miles since 1985, so that many of them are sitting in deeper water with more ice in contact with warmer water making it harder for glaciers to grow back.  At this point, even if the climate reverses its trend, the ice sheet will continue to lose mass.

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Warming Greenland ice sheet passes point of no return

Photo, posted August 27, 2015, courtesy of Joxean Koret via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Endangered Language Species

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There are approximately 7,000 languages spoken in the world today but only about half of them are expected to survive this century.  There are many factors contributing to the decline in languages.  Perhaps the most significant is globalization, which pushes countries and individuals to shift to national or international languages for economic reasons.   Other factors include the lack of support for regional languages in educational systems and mass media, persecution of minority linguistic groups by governments, and disruption of communities during war and emigration.

Predicting which languages will survive and which won’t is difficult.  A potential tipping point for languages is the same one affecting the survival of species:  climate change.  Many small linguistic communities are located on islands and coastlines that are vulnerable to hurricanes and rising sea levels.  Other communities live in places where increases in temperatures and erratic rainfall threaten traditional farming and fishing economies.

These climate-related changes will force communities to relocate,creating climate change refugees. Dispersing these people will lead to the splintering of linguistic communities and the need for the use of other languages.  Such changes will place additional pressures on languages that are already struggling to survive.

There are endangered languages in many places around the world.  Some are exotic such as the island of Sulawesi in Indonesia, which is home to dozens of distinct languages spoken by no more than a few thousand people. Others are much closer to home, such as in indigenous communities in Canada.

The rich tapestry of human language is just another of many things threatened by the changing climate.

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The Conversation: The impact of climate change on language loss

Photo, posted May 19, 2009, courtesy of Flickr. 

Earth Wise is a production of WAMC Northeast Public Radio.

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