tipping points

Positive tipping points and climate

January 29, 2024 By EarthWise Leave a Comment

We often hear about tipping points and climate change. Tipping points are critical thresholds that, when crossed, lead to large, accelerating, and often irreversible changes. Some of the ones of concern with the climate are thawing permafrost, melting glaciers and ice sheets, and global temperatures reaching certain levels. These are all tipping points that are essential to avoid.

A study published in the journal One Earth by researchers at the University of Exeter in the UK contends that in order to avoid the severe consequences of climate change, we need to trigger some positive tipping points.

Many climate-friendly changes are happening too slowly. Triggering positive tipping points is a way to rapidly reach the high levels of decarbonization required to avoid triggering the negative tipping points of great concern.

Reaching a positive tipping point is a way that beneficial changes can rapidly gain momentum. One example is the adoption of electric vehicles. It has clearly reached a tipping point across Scandinavia and has happened rapidly. Norway has managed to transition the market share of electric vehicles from under 10% to nearly 90% in less than 10 years. At some point, everybody wanted an electric car. This is evidence that positive tipping points can happen.

Many of the other forms of decarbonization need to move from their current level of adoption to rapid expansion. A combination of affordability, attractiveness, availability, and political will are needed to trigger tipping points. Exactly what those tipping point are is not necessarily known, but unless something accelerates the current pace of change, it will be very difficult to prevent negative climate tipping points from changing the world in destructive ways.

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Positive tipping points must be triggered to solve climate crisis

Photo, posted July 8, 2023, courtesy of Michael Swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Species Tipping Points | Earth Wise

June 22, 2023 By EarthWise Leave a Comment

In climate science, tipping points are critical thresholds that, once crossed, lead to large and often irreversible changes in the climate system. For example, surpassing a 1.5 degree C rise in global warming has long been considered a tipping point for the planet.

According to a new study led by researchers from University College London, climate change will abruptly push species over tipping points as their geographic ranges reach unforeseen temperatures.

In the study, which was recently published in the journal Nature Ecology and Evolution, the research team analyzed data from more than 35,000 species of animals and seagrasses from every continent and ocean basin, alongside climate projections up to 2100. The researchers found a consistent trend: for many animals, the thermal exposure threshold will be crossed for much of their geographic range within the same decade.

The thermal exposure threshold is defined as the first five consecutive years where temperatures consistently exceed the most extreme monthly temperature experienced by a species across its geographic range over recent history.

The researchers also found that the extent of global warming will make a big difference for animals. If the planet warms by just 1.5°C, 15% of species studied will be at risk of experiencing unfamiliarly hot temperatures across at least 30% of their current geographic range in a single decade. But this figure will double to 30% of species at 2.5°C of warming.

Since their data provides an early warning system, the researchers hope that their findings will help species conservation efforts.

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Climate change to push species over abrupt tipping points

Photo, posted May 27, 2017, courtesy of Sarah Lemarié via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The State Of The Birds | Earth Wise

November 28, 2022 By EarthWise Leave a Comment

The U.S. Committee of the North American Bird Conservation Initiative has published the State of the Birds 2022, an assessment of bird populations in North America. The news is not good. The report identifies 70 Tipping Point species, which are those that have lost half or more of their breeding population since 1970 and are on track to lose another half or more in the next 50 years. According to research published in Science in 2019, the United States and Canada have lost 3 billion breeding birds since 1970, which is about a quarter of the total population.

More than half of the bird species in the United States are in decline. According to the Conservation Initiative, the tipping point species in particular require proactive conservation protections to avoid becoming endangered. Species that inhabit grasslands are declining more rapidly, while waterfowl like ducks and geese are actually increasing. That increase is most likely a result of the investments in conservation funded by the hunting industry.

Those waterfowl gains demonstrate that when there are concerted efforts to protect and promote bird populations, positve changes can happen. Some say that protecting birds is not a high priority given all the other crises in the world, but what is good for birds is also good for people. For example, planting trees and other vegetation to enhance bird habitat also helps to sequester carbon, protect coastlines from storm surges, increase groundwater recharge, and reduce urban heating effects.

The loss of 3 billion birds is a major biodiversity crisis and requires action. Bird conservation benefits wildlife, people, entire ecosystems, and our planet.

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What’s Good for Birds Is Good for People and the Planet. But More Than Half of Bird Species in the U.S. Are in Decline

Photo, posted November 4, 2020, courtesy of Tom Koerner/U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Short-Lived Climate Forcing Pollutants | Earth Wise

March 9, 2021 By EarthWise Leave a Comment

When talking about the causes of climate warming, it is common practice to bundle together various pollutants and express their effects in terms of “CO2 equivalence.” This involves comparing climate effects of the pollutants on a 100-year timescale. Recent research from the Institute for Advanced Sustainability Studies in Germany points out the problems with this approach.

One of the worst qualities of carbon dioxide is that it accumulates in the atmosphere. Once it gets there, it stays there for anywhere from decades to millennia. On the other hand, short-lived climate forcing pollutants – or SLCPs – stay in the atmosphere for significantly shorter periods. However, some of these are far more effective at trapping heat in the atmosphere. As a result, the atmosphere and climate system react much more quickly to reductions in the emission of these pollutants.

The IASS research study determined that reducing SLCP emissions is an important way to slow near-term climate warming as well as having other positive benefits such as reducing air pollution and improving crop yields. A number of studies indicate that a rapid reduction in SLCP emissions could slow the rate of climate change and reduce the risk of triggering dangerous and potentially irreversible climate tipping points.

Examples of SLCPs are the methane gas emitted from landfills and hydrofluorocarbons that are still widely used as coolants. HFCs only persist in the atmosphere for 15 years but are nearly 4,000 times more effective in trapping heat over a 20-year period.

In order to mitigate the most harmful consequences of climate change, we need to minimize both the near-term climate impacts of SLCPs and the long-term climate impacts of carbon dioxide.

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More Than Just CO2: It’s Time To Tackle Short-Lived Climate-Forcing Pollutants

Photo, posted March 10, 2020, courtesy of Jonathan Cutrer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.