Ecology, Climate Change and Related News

Conservation Science for a Healthy Planet

Category Archive: Climate Change

  1. Farming with crops and rocks to address global climate, food and soil security

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    February 2018

    ABSTRACT: The magnitude of future climate change could be moderated by immediately reducing the amount of CO2 entering the atmosphere as a result of energy generation and by adopting strategies that actively remove CO2 from it. Biogeochemical improvement of soils by adding crushed, fast-reacting silicate rocks to croplands is one such CO2-removal strategy. This approach has the potential to improve crop production, increase protection from pests and diseases, and restore soil fertility and structure.

    Managed croplands worldwide are already equipped for frequent rock dust additions to soils, making rapid adoption at scale feasible, and the potential benefits could generate financial incentives for widespread adoption in the agricultural sector. However, there are still obstacles to be surmounted. Audited field-scale assessments of the efficacy of CO2 capture are urgently required together with detailed environmental monitoring. A cost-effective way to meet the rock requirements for CO2 removal must be found, possibly involving the recycling of silicate waste materials. Finally, issues of public perception, trust and acceptance must also be addressed.

    Beerling, DJ, et al, Jim Hansen. Farming with crops and rocks to address global climate, food and soil security. Nature Plants

  2. Soil fungi may help determine the resilience of forests to environmental change

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    • Association of ectomycorrhizal trees with high carbon-to-nitrogen ratio soils across temperate forests is driven by smaller nitrogen not larger carbon stocks
    • the findings suggest that the mycorrhizal guild could be an emerging “functional trait” that define species in terms of their ecological roles — how they interact with the environment and with other species.
    • they are particularly valuable to scientists who are monitoring environmental responses to climate change as they can tell us how the ecosystem is responding
    • understanding how mycorrhizal relationships impact ecosystems will help us predict how forests will respond to global change.

    March 16, 2018 University of California – Santa Cruz Read full ScienceDaily article here

    A new study reveals that soil fungi could play a significant role in the ability of forests to adapt to environmental change. [The study used a] “big data” approach to investigating the role of symbiotic fungi in tree migration in forests across the eastern United States.

    …In forests, tree growth largely depends on the nutrients available in the soil, while the transfer of carbon through roots to the soil regulates ecosystem processes. Mycorrhizal (“MY-koe-RY-zull”) fungi grow on the roots of most plants and drive the nutrient-carbon exchange between plants and soil: They take up carbon resources from their hosts and provide soil nutrients that plants need.

    The two most common fungi associated with forest trees are: ectomycorrhizal (ECM), which grow on conifers, including pines, as well as oaks and beeches; and arbuscular (AM), which grow on most nonconifers, such as maples.

    ...soil carbon-to-nitrogen ratios increase with greater ECM dominance — even after accounting for climate, soil texture, and foliar nitrogen. Moreover, ECM dominance is more associated with low soil nitrogen rather than high soil carbon.

    …”These findings suggest that AM and ECM trees have differential success along nitrogen fertility gradients, or perhaps that AM and ECM trees promote differences in cycling rates of carbon and nitrogen because of traits associated with nitrogen acquisition,” he said. “Both processes may occur simultaneously, leading to a self-reinforcing positive plant-soil feedback.”

    Zhu’s findings suggest that the mycorrhizal guild could be an emerging “functional trait.”

    Functional traits are those that define species in terms of their ecological roles — how they interact with the environment and with other species. As such, they are predictable and easily measured from the ground or by satellite, which makes them particularly valuable to scientists who are monitoring environmental responses to climate change. “They tell us how the ecosystem is responding,” said Zhu.

    Kai Zhu, M. Luke McCormack, Richard A. Lankau, J. Franklin Egan, Nina Wurzburger. Association of ectomycorrhizal trees with high carbon-to-nitrogen ratio soils across temperate forests is driven by smaller nitrogen not larger carbon stocks. Journal of Ecology, 2018; 106 (2): 524 DOI: 10.1111/1365-2745.12918

  3. Pacific Heat Wave Known As ‘The Blob’ Appears To Be In Retreat

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    • The transition from “the Blob” to cooler water was observed for 2 months but the deep water is still very warm.

    by March 15, 2018  Read OPB/EarthFix article here

    ….A report from the National Oceanic and Atmospheric Administration (NOAA) outlined the latest ocean observations for the organization that sets salmon catch limits off the West Coast. The Pacific Fishery Management Council will set those limits in early April.

    The extended marine heatwave of the past few years has been nicknamed “the Blob.”

    ….Within the past year, the El Niño effect has dissipated, and other longer-term climate cycles are shifting back toward a more average level.

    “We finally saw some of those northern, fat copepods off the coast of Oregon, which was a very good signal,” said Jennifer Fisher, a researcher with NOAA and Oregon State University. “But the caveat to that is that we saw that transition for only a couple months.”

    Fisher says they will test again this coming summer to see if the trend holds.

    Fisher’s tempered optimism is not unique. Elsewhere scientists are still finding lingering effects of the Blob.

    “If you look in the North Pacific, the deep water is still very warm,” Toby Garfield said. “Which means there’s still a lot of heat being stored.”

    In addition, last summer, there was a major low-oxygen event that caused crab die-offs….

  4. Increased risk of a shutdown of ocean convection posed by warm North Atlantic summers; increased freshwater flow into ocean already weakening subpolar deep convection

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    • Long-term observations show that increased surface freshening has weakened deep water convection in the subpolar North Atlantic.
    • There is a clear correlation between the sea surface temperatures in the Irminger Sea in summer, the amount of surface freshwater in this region— and the atmospheric conditions and onset of convection in the following winter.
    • [Note: this could have devastating impacts on weather -see this study for example.]

    March 13, 2018 Helmholtz Centre for Ocean Research Kiel (GEOMAR) Read full ScienceDaily article here

    The temperature and salinity of seawater are key drivers for the global ocean circulation system. Warm and saline water transported poleward cools at the surface when it reaches high latitudes and becomes denser and subsequently sinks into the deep ocean. This process is called convection. At depth, the water is circulated back towards the equator drawing new water masses behind it. Deep convection occurs only in a few regions around the globe, including the Irminger Sea and the Labrador Sea near Greenland. But what happens if additional freshwater, for example from melting glaciers, enters this system? Model calculations predict a possible weakening of deep convection, but so far this could not be confirmed by direct observations.

    By using long-term observations, scientists … have now shown that freshwater has already impacted convection in the last decade. The results have been published in the international journal Nature Climate Change….

    …”In case that warm summers with increased surface freshwater occur within extended warm periods, the ocean loses less heat in the following winter. As a result, the fresh surface layer that formed in summer remains stable for a longer time resulting in a delayed onset of convection,” says Dr. Oltmanns.

    Marilena Oltmanns, Johannes Karstensen, Jürgen Fischer. Increased risk of a shutdown of ocean convection posed by warm North Atlantic summers. Nature Climate Change, 2018; DOI: 10.1038/s41558-018-0105-1

  5. Climate change threatens half of plant and animal species in world’s biodiversity hotspots

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    • Half of plant and animal species at risk from climate change in world’s most important natural places
    • The Amazon, Miombo Woodlands in Southern Africa, and south-west Australia will be among the most affected places in the world, according to comprehensive new paper and report commissioned by WWF

    March 13 2018 University of East Anglia Read more from ScienceDaily here

    Up to half of plant and animal species in the world’s most naturally rich areas, such as the Amazon and the Galapagos, could face local extinction by the turn of the century due to climate change if carbon emissions continue to rise unchecked. Even if the Paris Climate Agreement 2°C target is met, these places could lose 25% of their species according to a landmark new study by the University of East Anglia, the James Cook University, and WWF.

    Published today in the journal Climatic Change and just ahead of Earth Hour, the world’s largest environmental event, researchers examined the impact of climate change on nearly 80,000 plant and animal species in 35 of the world’s most diverse and naturally wildlife-rich areas….

    ….If there was a 4.5°C global mean temperature rise, the climates in these areas are projected to become unsuitable for many the plants and animals that currently live there meaning:

    • Up to 90% of amphibians, 86% of birds and 80% of mammals could potentially become locally extinct in the Miombo Woodlands, Southern Africa
    • The Amazon could lose 69% of its plant species
    • In south-west Australia 89% of amphibians could become locally extinct
    • 60% of all species are at risk of localised extinction in Madagascar
    • The Fynbos in the Western Cape Region of South Africa, which is experiencing a drought that has led to water shortages in Cape Town, could face localised extinctions of a third of its species, many of which are unique to that region…..

    ….Dr Jeff Price, coordinator of the Wallace Initiative and also from UEA, said: “This research provides a view on the differing spatial impacts of climate change on biodiversity. It shows the benefits of combining citizen science with the research and resources of highly-ranked Universities to assist an NGO with their conservation activities.”

    R. Warren, J. Price, J. VanDerWal, S. Cornelius, H. Sohl. The implications of the United Nations Paris Agreement on climate change for globally significant biodiversity areas. Climatic Change, 2018; DOI: 10.1007/s10584-018-2158-6

    Also see related World Wildlife Fund publication: Wildlife in a Warming World: The Effects of Climate Change on Biodiversity


  6. Warm Arctic? Expect Northeast Blizzards: What 7 Decades of Weather Data Show

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    • When Arctic temperatures spike, extreme winter weather is 2 to 4 times more likely in Boston and New York, while the West tends to be warmer, a new study shows.
    • Heavy snowfalls are generally more frequent since 1990, and in many cities the most extreme snowfalls have occurred primarily during recent decades.
    • Declining temperature contrast between the Arctic and the mid-latitudes leads to a wavier jet stream that disrupts normal weather patterns.
  7. Tree Farms Will Not Save Us from Global Warming

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    • Plantations would have to be massive in scale, and their value is still unproven.
    • Relying on BECCS-bioenergy with carbon capture and storage- via the land system is a very high risk to the Earth system in general.
    • The Intergovernmental Panel on Climate Change, in its Fifth Assessment Report, presented more than 100 modeled scenarios that it said had a high likelihood of keeping global temperatures within 2 degrees Celsius of preindustrial levels. Nearly all of them assumed that negative emissions technology would be viable and widely used, particularly BECCS.

    By Chelsea Harvey, E&E News on March 13, 2018 read full Scientific American reprint here

    ….a much bigger geoengineering strategy that some experts hope could reduce global emissions by removing carbon dioxide from the atmosphere [is] known as “negative emissions”…

    The idea calls for massive plantations of trees and other crops to draw carbon dioxide out of the air. The trees could then be harvested for the production of energy or biofuels, with carbon capture technology used to sequester their emissions. The whole process would be carbon-negative. This could theoretically cool the climate. But it would have to be done at a massive scale.

    It’s still almost an entirely hypothetical concept. But it has rapidly risen to prominence as a strategy for meeting the world’s climate targets established under the Paris Agreement. It’s called “bioenergy with carbon capture and storage,” or BECCS….

    study published in the journal Nature Climate Change in January is among the latest to raise doubts. It suggests that the large-scale deployment of BECCS—which calls for massive, managed plantations of trees—would likely require an unsustainable use of land, water and other resources.

    “Our main message is that really relying on BECCS via the land system is a very high risk to the Earth system in general,” said the paper’s lead author, Vera Heck of the Potsdam Institute for Climate Impact Research in Germany.

    The research relies on the idea of “planetary boundaries,” a concept first developed by scientists in 2009. It describes nine environmental thresholds, from freshwater use and land changes to ocean acidification. Pushing any of these boundaries too far, the framework suggests, could result in irreversible consequences for Earth systems. Climate change itself is listed as one of the planetary boundaries….

    …Just this month, the European Academies Science Advisory Council released a report warning against unrealistic assumptions about carbon dioxide removal, or CDR.

    …A recent study in the Proceedings of the National Academy of Sciences points out that nations need to have the resources to transport harvested biomass to processing facilities if they’re going to use it for energy. And once it’s been burned, these nations must also have access to locations suitable for storing the captured carbon dioxide underground.

    …As experts call for greater caution in the assumptions being made about future technology, modelers may explore more scenarios in which negative emissions are less aggressively deployed….

  8. Sinking land will exacerbate flooding from sea level rise in Bay Area

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    • Subsidence combined with sea level rise around San Francisco Bay could double flood-risk area

    March 7, 2018 University of California – Berkeley

    …A new study of subsidence around San Francisco Bay shows that for conservative estimates of sea level rise, twice the area is in danger of flooding by 2100 than previously thought. Some landfill is sinking 10 mm per year, threatening the airport and parts of Silicon Valley…

    [Note: The USGS CoSMoS modeling that underlies the Our Coast Our Future tool (developed by Point Blue, USGS, and others) accounts for uncertainty in spatially variable vertical land motion for the SF Bay Region– see “Flood Potential” topic in section 1 in OCOF flood map. The vertical land motion component that went into understanding the uncertainty of the flood mapping for original SF Bay OCOF work (image below) was developed by the same author, Roland Burgmann, through the NOAA’s National Estuarine Research Reserve. This new paper is a refinement of these data.]

    “We are only looking at a scenario where we raise the bathtub water a little bit higher and look where the water level would stand,” said senior author Roland Bürgmann, a UC Berkeley professor of earth and planetary science. “But what if we have a 100-year storm, or king tides or other scenarios of peak water-level change? We are providing an average; the actual area that would be flooded by peak rainfall and runoff and storm surges is much larger.”

    …”Accurately measuring vertical land motion is an essential component for developing robust projections of flooding exposure for coastal communities worldwide,” said Patrick Barnard, a research geologist with the U.S. Geological Survey in Menlo Park [and OCOF PI]. “This work is an important step forward in providing coastal managers with increasingly more detailed information on the impacts of climate change, and therefore directly supports informed decision-making that can mitigate future impacts.”….

    Sf Bay Flood potential

  9. Climate Change Threatens Major Crops in California

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    • California produces over a third of the country’s vegetables and two-thirds of its fruits and nuts.
    • By the end of the century California’s climate will no longer be able to support the state’s major crops, including orchards.

    by Ahmel Ahmed KQED Feb 26 2018  read full article here

    California currently provides two-thirds of the country’s fruits and nuts, but according to a new study published Tuesday, by the end of the century California’s climate will no longer be able to support the state’s major crops, including orchards.

    The report, published in “Agronomy,” warns that the increased rate and scale of climate change is “beyond the realm of experience” for the agricultural community, and unless farmers take urgent measures, the consequences could threaten national food security.

    “For California, as an agricultural leader for various commodities, impacts on agricultural production due to climate change would not only translate into national food security issues but also economic impacts that could disrupt state and national commodity systems,” the report warns.

    The study, led by researchers from the University of California, Merced and Davis campuses, looked at past and current trends in California’s climate and examined what impact record low levels of snowpack, and extreme events such as drought will have on crop yields over time…

    Tapan B. Pathak , Mahesh L. Maskey, Jeffery A. Dahlberg, Faith Kearn, Khaled M. Bali and Daniele Zaccaria. Climate Change Trends and Impacts on California Agriculture: A Detailed Review. Agronomy 2018, 8(3), 25; doi:10.3390/agronomy8030025

    Abstract: California is a global leader in the agricultural sector and produces more than 400 types of commodities. The state produces over a third of the country’s vegetables and two-thirds of its fruits and nuts. Despite being highly productive, current and future climate change poses many challenges to the agricultural sector. This paper provides a summary of the current state of knowledge on historical and future trends in climate and their impacts on California agriculture. We present a synthesis of climate change impacts on California agriculture in the context of: (1) historic trends and projected changes in temperature, precipitation, snowpack, heat waves, drought, and flood events; and (2) consequent impacts on crop yields, chill hours, pests and diseases, and agricultural vulnerability to climate risks. Finally, we highlight important findings and directions for future research and implementation. The detailed review presented in this paper provides sufficient evidence that the climate in California has changed significantly and is expected to continue changing in the future, and justifies the urgency and importance of enhancing the adaptive capacity of agriculture and reducing vulnerability to climate change. Since agriculture in California is very diverse and each crop responds to climate differently, climate adaptation research should be locally focused along with effective stakeholder engagement and systematic outreach efforts for effective adoption and implementation. The expected readership of this paper includes local stakeholders, researchers, state and national agencies, and international communities interested in learning about climate change and California’s agriculture. View Full-Text