Hungry birds as climate change drives food ‘mismatch’

  • With spring coming earlier due to climate change, leaves and caterpillars emerge earlier and birds need to breed earlier to avoid being mismatched.  Researchers in England found that the earlier the spring, the less able birds are to do this.

April 23, 2018 University of Exeter Read full ScienceDaily article here

Warmer springs create a “mismatch” where hungry chicks hatch too late to feast on abundant caterpillars, new research shows.

With continued spring warming expected due to climate change, scientists say hatching of forest birds will be “increasingly mismatched” with peaks in caterpillar numbers.

The researchers, from the RSPB and the universities of Exeter and Edinburgh, used data collected across the UK — largely by citizen scientists — to study spring emergence of oak tree leaves and caterpillars, and timing of nesting by three bird species: blue tits, great tits and pied flycatchers….

…”Forests have a short peak in caterpillar abundance, and some forest birds time their breeding so this coincides with the time when their chicks are hungriest,” said Dr Malcolm Burgess, of the University of Exeter and the RSPB. “With spring coming earlier due to climate change, leaves and caterpillars emerge earlier and birds need to breed earlier to avoid being mismatched.

“We found that the earlier the spring, the less able birds are to do this. The biggest mismatch was among pied flycatchers — as migratory birds, they are not in the UK in winter and therefore are much less able to respond to earlier spring weather.”…

Malcolm D. Burgess, Ken W. Smith, Karl L. Evans, Dave Leech, James W. Pearce-Higgins, Claire J. Branston, Kevin Briggs, John R. Clark, Chris R. du Feu, Kate Lewthwaite, Ruedi G. Nager, Ben C. Sheldon, Jeremy A. Smith, Robin C. Whytock, Stephen G. Willis, Albert B. Phillimore. Tritrophic phenological match–mismatch in space and time. Nature Ecology & Evolution, 2018; DOI: 10.1038/s41559-018-0543-1

Increasing precipitation extremes in California; likelihood of 40 day flood event will increase significantly over decades ahead

By Daniel Swain April 22 2018 Read full CA Weather Blog article here

Previous studies have found that future changes in California’s overall average annual precipitation are likely to be fairly modest, even under rather extreme global warming scenarios. Most climate models suggest that the boundary between mean wetting (in the already moist mid-latitude regions to the north) and mean drying (in the already arid subtropics to the south) in a warming world will likely fall somewhere over California—which increases uncertainty regarding whether the region will become slightly wetter or slightly drier on average. The notion that California’s average precipitation might not change much in the future is actually somewhat surprising, as there is high confidence that other “mediterranean” climate regions on Earth will experience progressively less precipitation as the world warms and the region of stable subtropical influence expands. As we demonstrate in our new research, however, these small shifts in average precipitation mask profound changes in the character of California precipitation. We find that the occurrence of both extreme wet and extreme dry events in California—and of rapid transitions between the two—will likely increase with atmospheric greenhouse gas concentrations. The rising risk of historically unprecedented precipitation extremes will seriously test California’s existing water storage, distribution, and flood protection infrastructure….

….As most of us already know, global climate is presently changing at a rate faster than has occurred in thousands of years, almost exclusively due to the emission of greenhouse gases (like carbon dioxide) into the Earth’s atmosphere. But the Earth is not warming at the same rate everywhere, and regional differences are subject to considerably more scientific uncertainty than the overall global warming trend. That’s especially true for many of the complex meteorological phenomena that we care most about: the dramatic storms, floods, heatwaves, and droughts that tend to have the largest impacts upon human lives, economies, physical infrastructure, and the environment….

….Our new analysis suggests that the risk of an extreme “sub-seasonal” 40-day precipitation event similar in magnitude to that which caused the 1862 flood will rise substantially as the climate warms. By the end of the 21st century, we find a 300 – 400+ % increase in the relative risk of such an event across the entire state. One specific statistic that my colleagues and I found particularly eyebrow-raising: on our current emissions trajectory, at least one occurrence of an 1862-level precipitation event is more likely than not over the next 40 years (between 2018 and 2060), with multiple occurrences plausible between now and the end of the century. In practical terms, this means that what is today considered to be the “200-year flood”—an event that would overwhelm the vast majority of California’s flood defenses and water infrastructure—will become the “40-50 year flood” in the coming decades….

….Our research suggests that the frequency of such “precipitation whiplash” events—in which California experiences a very dry year followed immediately by a very wet year—will increase considerably as the climate warms. We find anywhere from a 25% increase in far northern California to over a 100% increase over far southern California in the frequency of these dry-to-wet whiplash events (of a magnitude that has historically occurred about four times per century). …

Swain, D. L., B. Langenbrunner, J. D. Neelin, and A. Hall, “Increasing precipitation volatility in 21st-century-California,” Nature Climate Change, doi:10.1038/s41558-018-0140-y, 2018.

Nature-based solutions can prevent $50 billion in Gulf Coast flood damages– Restoration of marshes and oyster reefs are among the most cost-effective solutions

  • Wetland and reef restoration can yield benefit-to-cost ratios greater than seven to one, meaning more than $7 in direct flood-reduction benefits for every $1 spent on restoration.
  • Future flood risks from coastal hazards will grow, and that the major driver of risk in the Gulf is coastal development, particularly for the most extreme and costly events: the more people and property exposed to coastal hazards, the greater the flooding risk. Climate change, however, will result in more frequent losses. Events causing $100 billion in damages may become approximately three times more frequent in the future, the study found.

April 12, 2018 University of California – Santa Cruz Read full ScienceDaily article here

While coastal development and climate change are increasing the risk of flooding for communities along the US Gulf Coast, restoration of marshes and oyster reefs are among the most cost-effective solutions for reducing those risks, according to a new study.

…the study compares the cost effectiveness of nature-based and artificial solutions for flood reduction across the Gulf of Mexico. The results clearly demonstrate the value of nature-based solutions such as marsh and oyster-reef restoration. Overall, wetland and reef restoration can yield benefit-to-cost ratios greater than seven to one, meaning more than $7 in direct flood-reduction benefits for every $1 spent on restoration. Many artificial solutions (such as levees and home elevation) have benefit-to-cost ratios near or below one-to-one; their benefits can be high, but they are expensive to implement at scale.

The study was led by researchers at UC Santa Cruz, the Nature Conservancy, and the Swiss Federal Institute of Technology at ETH Zurich. It applied the Economics of Climate Adaptation (ECA) approach, which was developed by reinsurance company Swiss Re and partners to understand what drives coastal risk and to evaluate the cost-effectiveness of adaptation options…..

…The new study quantified the flood risks to people and property for the entire U.S. coast of the Gulf of Mexico under current and future climate scenarios and economic growth projections. It showed that future flood risks from coastal hazards will grow, and that the major driver of risk in the Gulf is coastal development, particularly for the most extreme and costly events: the more people and property exposed to coastal hazards, the greater the flooding risk. Climate change, however, will result in more frequent losses. Events causing $100 billion in damages may become approximately three times more frequent in the future, the study found.

….”We show that nature-based measures for flood reduction can be considered right alongside artificial or gray measures such as seawalls in industry-based benefit-cost models. This removes a major impediment for engineers, insurers, and risk management agencies for building coastal resilience more naturally,” said project team leader Michael Beck, lead marine scientist at the Nature Conservancy and a research professor at UC Santa Cruz.

…The team developed open-source software based in part on Swiss Re’s natural catastrophe model to assess flood risks and adaptation solutions. All of the results and maps showing the cost effectiveness of adaptation solutions under future climate change and development scenarios are available in an interactive mapper available online at CoastalResilience.org.

Borja G. Reguero, Michael W. Beck, David N. Bresch, Juliano Calil, Imen Meliane. Comparing the cost effectiveness of nature-based and coastal adaptation: A case study from the Gulf Coast of the United States. PLOS ONE, 2018; 13 (4): e0192132 DOI: 10.1371/journal.pone.0192132

Is it worth paying for carbon offsets next time you fly?

  • Does it work?  Even if you pay, you’re not stopping carbon dioxide produced by your flight from entering the atmosphere.
  • Reduce your number of flights per year. And if you must fly, do research and choose to fly with an airline that has a good emission reduction record. And if your airline doesn’t have a reputable scheme, you can source your own airline carbon emission program.
  • An alternative is “insetting”, or start your own carbon scheme, she added. “You can apply it to yourself. Do you offset every one of your flights, or do you save the money to help buy solar panels for your house?”

by Belinda Smith April 11 2018 Read full Australia ABC article here

When booking flights online you may be offered the option to offset your share of carbon emissions for a few extra dollars.

But where does the money go, what is it used for, and is it worth ticking that carbon offset box?

The option is there because aviation is responsible for about 2 per cent of global carbon dioxide emissions.

In 2016, Australia’s domestic and international civil aviation sector released the equivalent of 22 million tonnes of carbon dioxide.

As a result, about a third of airlines offer some form of carbon offsetting, where customers pay a few extra dollars into a scheme which carries out environmental improvement projects….

…So, is it worth paying for carbon offsets?

Yes … insofar as it’s better than nothing, said James Higham from the University of Otago in New Zealand. “On the positive side of things, carbon offsetting does, perhaps, prod users to think about their personal carbon profile.”

But even if you pay, you’re not stopping carbon dioxide produced by your flight from entering the atmosphere.

Land-based carbon offsetting, such as planting trees, might help suck in some atmospheric carbon dioxide, but nowhere near as much as flights churn out.

“If you plant a tree, or plant a million trees, that doesn’t really solve the problem because the carbon has been emitted and it’s in the atmosphere,” Professor Higham said.

“[The trees] may absorb some of the carbon dioxide, but then you have to maintain those trees….

….What else can flyers do to reduce their carbon footprint?

“We shouldn’t be flying as much,” Professor Ritchie said. “Let’s be clear about that.” Professor Higham agrees. “We need to really think about air travel,” he said. “I’m not saying for a minute that people stop flying and I’m not saying there should be less tourism.

If you must fly, try to do a bit of research and choose to fly with an airline that has a good emission reduction record, Professor Becken said. And if your airline doesn’t have a reputable scheme, you can source your own airline carbon emission program.

There are plenty of not-for-profit organisations such as Atmosfair in Germany, MyClimate in Switzerland and Climate Care in the UK that calculate your carbon offset payments and direct that money to their own projects.

An alternative to offsetting is “insetting”, or start your own carbon scheme, she added. “You can apply it to yourself. Do you offset every one of your flights, or do you save the money to help buy solar panels for your house?”

 

Hotter, longer, more frequent — marine heatwaves on the rise

  • From 1925-2016, the study found the frequency of marine heatwaves had increased on average by 34% and the length of each heatwave had increased by 17%. Together this led to a 54% increase in the number of marine heatwave days every year.

April 10, 2018 University of New South Wales

We know heatwaves over land have been increasing, but now new research reveals globally marine heatwaves have also been increasing in length, number and intensity over the past century. More intriguing still, this trend has accelerated markedly since 1982.

…Persistent warm water in the north Pacific from 2014-2016 led to fishery closures, mass strandings of marine mammals and harmful algal blooms along coastlines. That heatwave even changed large-scale weather patterns in the Pacific Northwest.

More recently still, Tasmania’s intense marine heatwave in 2016 led to disease outbreaks and slowing in growth rates across aquaculture industries….

….”With more than 90% of the heat from human caused global warming going into our oceans, it is likely marine heatwaves will continue to increase. The next key stage for our research is to quantify exactly how much they may change.

“The results of these projections are likely to have significant implications for how our environment and economies adapt to this changing world.”…

Eric C. J. Oliver, Markus G. Donat, Michael T. Burrows, Pippa J. Moore, Dan A. Smale, Lisa V. Alexander, Jessica A. Benthuysen, Ming Feng, Alex Sen Gupta, Alistair J. Hobday, Neil J. Holbrook, Sarah E. Perkins-Kirkpatrick, Hillary A. Scannell, Sandra C. Straub, Thomas Wernberg. Longer and more frequent marine heatwaves over the past century. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-03732-9

Atlantic Ocean circulation at weakest point in more than 1,500 years; that’s bad news

  • The oceans’ circulation hasn’t been this sluggish in 1,600 years. That’s bad news.

  • The research suggests that the Atlantic Meridional Overturning Circulation (AMOC) has weakened over the past 150 years by approximately 15 to 20 percent.

  • The present-day AMOC is exceptionally weak

April 11, 2018 Woods Hole Oceanographic Institution  Read full ScienceDaily article here and Washington Post coverage here

New research provides evidence that a key cog in the global ocean circulation system hasn’t been running at peak strength since the mid-1800s and is currently at its weakest point in the past 1,600 years. If the system continues to weaken, it could disrupt weather patterns from the United States and Europe to the African Sahel, and cause more rapid increase in sea level on the US East Coast.

….Another study in the same issue of Nature, led by Levke Ceasar and Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research, looked at climate model data and past sea-surface temperatures to reveal that AMOC has been weakening more rapidly since 1950 in response to recent global warming. Together, the two new studies provide complementary evidence that the present-day AMOC is exceptionally weak, offering both a longer-term perspective as well as detailed insight into recent decadal changes….

When it comes to regulating global climate, the circulation of the Atlantic Ocean plays a key role. The constantly moving system of deep-water circulation, sometimes referred to as the Global Ocean Conveyor Belt, sends warm, salty Gulf Stream water to the North Atlantic where it releases heat to the atmosphere and warms Western Europe. The cooler water then sinks to great depths and travels all the way to Antarctica and eventually circulates back up to the Gulf Stream.
Credit: Intergovernmental Panel on Climate Change
From Washington Post:

The Atlantic Ocean circulation that carries warmth into the Northern Hemisphere’s high latitudes is slowing down because of climate change, a team of scientists asserted Wednesday, suggesting one of the most feared consequences is already coming to pass.

The Atlantic meridional overturning circulation has declined in strength by 15 percent since the mid-20th century to a “new record low,” the scientists conclude in a peer-reviewed study published in the journal Nature. That’s a decrease of 3 million cubic meters of water per second, the equivalent of nearly 15 Amazon rivers.

The AMOC brings warm water from the equator up toward the Atlantic’s northern reaches and cold water back down through the deep ocean. The current is partly why Western Europe enjoys temperate weather, and meteorologists are linking changes in North Atlantic Ocean temperatures to recent summer heat waves.

The circulation is also critical for fisheries off the U.S. Atlantic coast, a key part of New England’s economy that have seen changes in recent years, with the cod fishery collapsing as lobster populations have boomed off the Maine coast.

David J. R. Thornalley, Delia W. Oppo, Pablo Ortega, Jon I. Robson, Chris M. Brierley, Renee Davis, Ian R. Hall, Paola Moffa-Sanchez, Neil L. Rose, Peter T. Spooner, Igor Yashayaev, Lloyd D. Keigwin. Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years. Nature, 2018; 556 (7700): 227 DOI: 10.1038/s41586-018-0007-4

L. Caesar, S. Rahmstorf, A. Robinson, G. Feulner & V. Saba. Observed fingerprint of a weakening Atlantic Ocean overturning circulationNature Volume 556pages191–196 (April 2018) doi:10.1038/s41586-018-0006-5

 

 


Grazing Management to Improve Soil Health- rotational grazing can improve soil health over continuous grazing strategies

  • Proper livestock grazing – which maintains and improves soil health – results in a series of interconnected positive outcomes including:
    • Soil densities and structure that allow root and water penetration of the entire soil profile.
    • Vigorous forage plants with capacity to develop and maintain extensive rooting systems.
    • A community of palatable forage plants with high rooting mass and depth.
    • Stable, resilient increases in primary productivity both above- and below- ground.

Ken Tate April 9 2018  Read full UC Rangelands article here

Grazing lands occupy nearly half the Earth’s land area, provide livelihoods for millions, and mitigate climate change via massive stores of carbon. Maintaining and restoring soil health is essential to ensuring these benefits in our ever changing environment.

Thus, there is substantial global interest in managing livestock grazing to improve soil health. Grazing is promoted by some as a panacea for sequestering carbon and mitigating climate change. In other cases, grazing is depicted as an ultimate driver of soil degradation….

…Our findings (Byrnes et al. 2018) suggest that rotational grazing can improve soil health over continuous grazing strategies. Decisions about grazing strategy and intensity significantly influence soil health outcomes, and site-specific conditions play important roles in shaping these out­comes.

Byrnes, R.C., D.J. Eastburn, K.W. Tate, and L.M. Roche*. 2018. A global meta-analysis of grazing impacts on soil health indicators. J. Environmental Quality. doi:10.2134/jeq2017.08.0313.

See previous post here.

Birds migrate away from diseases

  • Immune systems of migratory birds show a similarly low variation to that of European sedentary birds,a surprising result since migratory birds don’t have to resist diseases during breeding and during their migration.
  • To explain the surprising result, the researchers propose the idea that the costs associated with a strong and complex immune system could be much higher than anyone previously thought.

10 Apr 2018  Read full ScienceDaily article here

In a unique study, researchers have mapped the origins of migratory birds. They used the results to investigate and discover major differences in the immune systems of sedentary and migratory birds. The researchers conclude that migratory species benefit from leaving tropical areas when it is time to raise their young — as moving away from diseases in the tropics enables them to survive with a less costly immune system….

…”When the migratory birds breed, they have moved away from many diseases and therefore do not need an immune system that is equally varied. Another advantage is that the risk of damage caused by the immune system drops considerably if the immune system is less complex,” says researcher Emily O’Connor.

All vertebrates, including human beings, have an immune system built up in a similar way to that of birds. The Lund biologists therefore believe their findings could also be significant in a broader perspective.

Emily A. O’Connor, Charlie K. Cornwallis, Dennis Hasselquist, Jan-Åke Nilsson & Helena Westerdahl. The evolution of immunity in relation to colonization and migration. Nature Ecology and Evolution, 2018 DOI: 10.1038/s41559-018-0509-3

Can Responsible Grazing Make Beef Climate-Neutral?

  • New research found that the greenhouse gases sequestered in one grass-fed system balanced out those emitted by the cows, but some meatless advocates are skeptical.
 

There’s no denying Americans eat a lot of meat. In fact, the average U.S. citizen eats about 55 pounds of beef a year, including an estimated three hamburgers a week, and the United States Department of Agriculture (USDA) expects that amount to increase by about 3 percent by 2025. This heavy reliance on animal protein carries a big environmental footprint—livestock production contributes about 14.5 percent of global greenhouse gas (GHG) emissions, with beef constituting 41 percent of that figure, thanks to the methane cattle produce in the digestion process and the fact that overgrazing can release carbon stored in soils.

….A new five-year study that will be published in the May 2018 issue of the journal Agricultural Systems suggests that they can. Conducted by a team of researchers from Michigan State University (MSU) and the Union of Concerned Scientists (UCS), the study suggests that if cattle are managed in a certain way during the finishing phase, grassfed beef can be carbon-negative in the short term and carbon-neutral in the long term….

….“it is possible that long-term [adaptive multi-paddock grazing] AMP grazing finishing in the Upper Midwest could contribute considerably more to climate change mitigation and adaptation than previously thought.”

Rather than using the common method of continuous grazing, in which cattle remain on the same pasture for an entire grazing season, the researchers used the more labor-intensive method of AMP, which entails moving the cattle at intervals ranging from days to months, depending on the type of forage, weather, time of year, and other considerations. A herd of adult cattle on MSU grazing land served as their test population.

Though the study’s finding that strategic grazing can make a dent in the overall environmental impact of cattle runs counter to the widespread opinion among other researchers and climate activists, it is welcome news for advocates of regenerative agriculture.

…. Tara Garnett, a food systems analyst and the founder of the Food Climate Research Network (FCRN) at the University of Oxford in England, calls the MSU work “a really useful study,” but also observes that it is “unclear how far this approach will lead to the same results elsewhere.” The study authors, too, are careful to stress that their results apply to Upper Midwestern conditions, and using a similar method in other ecosystem types will require further tailored study. They also acknowledge that while degraded land properly managed can take up large amounts of carbon, the soil will eventually reach equilibrium (meaning it will reach its carbon limit), and estimates of how long that takes vary widely.

In addition, soil types and the many other aspects of climate and ecosystems in different regions require detailed understanding and granular management of grazing—something many beef producers may be unwilling to undertake. And grazing requires twice as much land as feedlots….

…. One very promising practice, she said, is for ranchers to enlist farmers in the beef finishing phase. One farmer was initially very skeptical, but after he had grown a series of cover crops to rest his wheat fields and used cattle to “harvest” them, leaving the residue on the fields, he discovered that the soil was improving rapidly, Carman said. Reduced fertilizer and pesticide inputs, together with the income from the pasturage fees, makes the next wheat crop less expensive to grow.

…. said Rowntree, “I hope our paper can give our industry, combined with policymakers, a lens that can potentially help. We’re not trying to pit one group against another.”

Carman also acknowledges the complexity at hand, but feels the benefits to the soil she has seen are important to take into account. “Livestock are partly to blame for a lot of ecological problems we’ve got,” she said. “But we couldn’t repair these problems without livestock.”

Paige L. Stanley, Jason E.Rowntree, David K.Beede, Marcia S.DeLonge, Michael W.Hamm. Impacts of soil carbon sequestration on life cycle greenhouse gas emissions in Midwestern USA beef finishing systems.  Agricultural Systems Volume 162, May 2018, Pages 249-258 https://doi.org/10.1016/j.agsy.2018.02.003

See previous post on this here. 

And related NPR story:

A Grass-Roots Movement For Healthy Soil Spreads Among Farmers

April 9 2018 America’s farmers are digging soil like never before. A movement for “regenerative agriculture” is dedicated to building healthier soil and could even lead to a new eco-label on food.

US power sector carbon emissions intensity drops to lowest on record

  • U.S. power plant emissions averaged 967 lb. CO2 per megawatt-hour (MWh) in 2017, which was down 3.1 percent from the prior year and down 26.8 percent from the annual value of 1,321 lb CO2 per MWh in 2005.

April 4, 2018 College of Engineering, Carnegie Mellon University Read full ScienceDaily article here

Researchers have announced the release of the 2018 Carnegie Mellon Power Sector Carbon Index. The Index tracks the environmental performance of US power producers and compares current emissions to more than two decades of historical data collected nationwide. This release marks the one-year anniversary of the Index, developed as a new metric to track power sector carbon emissions performance trends.

….The latest data revealed the following findings: U.S. power plant emissions averaged 967 lb. CO2 per megawatt-hour (MWh) in 2017, which was down 3.1 percent from the prior year and down 26.8 percent from the annual value of 1,321 lb CO2 per MWh in 2005. The result for 2016 was initially reported as 1,001 lb/MWh, but was later revised downward to 998 lb/MWh.