Climate Change

Real Climate
“RealClimate is a commentary site on climate science by working climate scientists for the interested public and journalists. We aim to provide a quick response to developing stories and provide the context sometimes missing in mainstream commentary. The discussion here is mostly restricted to scientific topics and will only rarely get involved in any political or economic implications of the science. All posts are signed by the author(s), except ‘group’ posts which are collective efforts from the whole team. This is a moderated forum.”

Underestimating the Challenges of Avoiding a Ghastly Future
Corey J. A. Bradshaw at al., 2021 Frontiers in Conservation Science “We report three major and confronting environmental issues that have received little attention and require urgent action. First, we review the evidence that future environmental conditions will be far more dangerous than currently believed. The scale of the threats to the biosphere and all its lifeforms—including humanity—is in fact so great that it is difficult to grasp for even well-informed experts. Second, we ask what political or economic system, or leadership, is prepared to handle the predicted disasters, or even capable of such action. Third, this dire situation places an extraordinary responsibility on scientists to speak out candidly and accurately when engaging with government, business, and the public. We especially draw attention to the lack of appreciation of the enormous challenges to creating a sustainable future. The added stresses to human health, wealth, and well-being will perversely diminish our political capacity to mitigate the erosion of ecosystem services on which society depends. The science underlying these issues is strong, but awareness is weak. Without fully appreciating and broadcasting the scale of the problems and the enormity of the solutions required, society will fail to achieve even modest sustainability goals.” Summary here

All five of Earth’s largest mass extinctions linked to global warming
On geologyglasgow.org.uk 12 Jun 2020 “Andrew Kerr at Cardiff University, UK is more enthusiastic. He has long argued that volcanic activity and associated effects such as global warming are the key drivers of mass extinctions. Keller says the finding means there might be a new odd one out among mass extinctions: the one we may currently be in is also due to warming, but the carbon dioxide responsible was produced by us, not volcanoes.”

Documentary warns of ‘catastrophic’ changes happening in Gulf of Maine
Steven Webb · CBC News · Posted: Jul 09, 2020

Developing a Research Agenda for Solar Geoengineering Strategies: Proceedings of a Workshop in Brief.
National Academies of Sciences, Engineering, and Medicine 2020. Washington, DC: The National Academies Press, 14 pp “Despite efforts to reduce greenhouse gas emissions, many countries’ efforts reduce emissions are falling short of targets needed to limit global warming and its associated negative impacts. While there is widespread agreement that continued efforts to reduce emissions and adapt to climate change are paramount, there is growing interest in “climate intervention” or “geoengineering” approaches, including those that reduce global warming by reflecting sunlight to cool Earth. In a workshop held in August 2019, the National Academies convened experts to inform a larger study on solar geoengineering. Workshop participants discussed the current status of, and future directions for research on solar geoengineering strategies, including stratospheric aerosol injection, marine cloud brightening, and cirrus cloud thinning. This publication summarizes the presentations and discussions for the workshop.”

Solar Geoengineering Research Governance: Proceedings of a Workshop—in Brief.
National Academies of Sciences, Engineering, and Medicine. 2020. Washington, DC: The National Academies Press, 10 pp “Despite efforts to reduce greenhouse gas emissions…[as above]. In a workshop held in September 2019, the National Academies convened experts to inform a larger study on solar geoengineering. Workshop participants discussed the governance of research at international, national, and sub-national scales and explored research governance mechanisms that might be applied to climate intervention research. This publication summarizes the presentations and discussions for the workshop.”

New study shows the last 100 years of warming is not natural
Scott Sutherland, Meteorologist/Science Writer for The Weather Network, July 25, 2019 “What’s Up In Climate Change? The unnatural warming of the past 100 years, contrails increase climate heating, and how Canada should tackle the ‘nature emergency'”

A dire perspective:
‘We’re doomed’: Mayer Hillman on the climate reality no one else will dare mention
Patrick Barkham in The Guardian Apr 26, 2018

A more optimistic perspective:
Missing the forest for the trees: In climate change fight, simplest solutions might be the most obvious
Nazim Cicek on CBC News Sep 29, 2019. “Study says 1.25 trillion trees could be planted worldwide to remove carbon — and Canada could be a leader”

Wildlife Collapse From Climate Change Is Predicted to Hit Suddenly and Sooner
By Catrin Einhorn in the NY Times, Apr 15, 2020. “Scientists found a “cliff edge” instead of the slippery slope they expected.”

Project Drawdown
Highly recommended. From their About page: “Founded in 2014, Project Drawdown® is a nonprofit organization that seeks to help the world reach “Drawdown”— the future point in time when levels of greenhouse gases in the atmosphere stop climbing and start to steadily decline. Since the 2017 publication of the New York Times bestseller, Drawdown, the organization has emerged as a leading resource for information and insight about climate solutions. We continue to develop that resource by conducting rigorous review and assessment of climate solutions, creating compelling and human communication across mediums, and partnering with efforts to accelerate climate solutions globally.”

We Need to Hear These Poor Trees Scream’: Unchecked Global Warming Means Big Trouble for Forests
BY BOB BERWYN, INSIDECLIMATE NEWS Apr 25, 2020 “New studies show drought and heat waves will cause massive die-offs, killing most trees alive today.”

Family Forests Are Key To Fighting Climate Change. But They Need Help.
Austyn Gaffney in the Huffington Post Apr 24, 2020 “Conservationists have a plan for families to transform their trees into weapons against the climate crisis, and Amazon just pledged $10 million”

Starving grasshoppers? How rising carbon dioxide levels may promote an ‘insect apocalypse’
By Elizabeth Pennisi Apr. 29, 2020

More On this page
ADAPTING TO CLIMATE CHANGE
REDUCING GHG EMISSIONS//INCREASING CARBON SQUESTRATION
CLIMATE CHANGE DYNAMICS
CARBON FO0TPRINT

Also view
nsforestnotes.ca/currentissues/BIOMASS/BIOFUELS & GHGS

ADAPTING TO CLIMATE CHANGE

Bur Oak

Bur Oak grown horticulturally at Grand Oaks on Grand Lake, Halifax Co., Nova Scotia. It occurs naturally in N.B. and elsewhere on the eastern seaboard, why not in N.S? There are a dozen species of oak in Massachussetts. Should we introduce this and other oaks species to anticipate climatic warming?

As climate changes, longleaf pines move north – with help
Timothy B. Wheeler on bayjoural.com Apr 17, 2020. “On Maryland’s Eastern Shore, an evergreen forest that’s never ventured so far north is slowly gaining a toehold in fields where until recently corn and soybeans grew. Spurred along by intentionally set but carefully controlled brush fires, hundreds of longleaf pines are now reaching for the sky along Plum Creek, a meandering tributary of the Nanticoke River.” It’s a practical trial in “Assisted Migration”

Starving grasshoppers? How rising carbon dioxide levels may promote an ‘insect apocalypse’

The climate sensitivity of carbon, timber, and species richness covaries with forest age in boreal–temperate North America
Dominik Thom et al (April 15, 2019).IN: Global Change Biology.
Climate change threatens the provisioning of forest ecosystem services and biodiversity (ESB). The climate sensitivity of ESB may vary with forest development from young to old‐growth conditions as structure and composition shift over time and space. This study addresses knowledge gaps hindering implementation of adaptive forest management strategies to sustain ESB. We focused on a number of ESB indicators to (a) analyze associations among carbon storage, timber growth rate, and species richness along a forest development gradient; (b) test the sensitivity of these associations to climatic changes; and (c) identify hotspots of climate sensitivity across the boreal–temperate forests of eastern North America. From pre‐existing databases and literature, we compiled a unique dataset of 18,507 forest plots. We used a full Bayesian framework to quantify responses of nine ESB indicators. The Bayesian models were used to assess the sensitivity of these indicators and their associations to projected increases in temperature and precipitation. We found the strongest association among the investigated ESB indicators in old forests (>170 years). These forests simultaneously support high levels of carbon storage, timber growth, and species richness. Older forests also exhibit low climate sensitivity of associations among ESB indicators as compared to younger forests. While regions with a currently low combined ESB performance benefitted from climate change, regions with a high ESB performance were particularly vulnerable to climate change. In particular, climate sensitivity was highest east and southeast of the Great Lakes, signaling potential priority areas for adaptive management. Our findings suggest that strategies aimed at enhancing the representation of older forest conditions at landscape scales will help sustain ESB in a changing world.
Thx to BB for forwarding this one

Forests of the Future in the Fundy Biosphere Reserve
Prepared by Ben Phillips, 2015. Posted on http://www.fundy-biosphere.ca/. “This project had three main objectives. The first was to use the best available data to map forest
climate change resiliency and create a climate change resiliency tree species list of use to
managers and anyone who plants trees. The second objective was to use the forest resiliency maps, combined with other conservation information to produce a climate change resilient forest corridor map. This map is to lay out a vision for wildlife corridors that can maintain integrity in the face of changing climates and the growing necessity of wildlife to shift territories, migrate and transition to more appropriate climatic zones. The third and final objective was to put the first two objectives into action. Three areas of low forest resiliency within the resilient forest corridors were to be planted with identified climate change resilient trees species appropriate for the local landscape. These areas are to act as future models of action for the local communities.”

Modelled Potential Species Distribution for Current and Projected Future Climates for the Acadian Forest Region of Nova Scotia, Canada
By C.P.A Bourque et al. 2010. Report to NSDNR. “…results for current and future climates indicate that boreal species in the Acadian forest of NS (e.g., balsam fir, black spruce) would be restricted to the cooler areas of the landscape, i.e., adjacent to cold water bodies (e.g., Bay of Fundy in the northwest and Atlantic Ocean on the south-to-northeast of the province) and high elevation areas, such as the Cape Breton Highlands and Cobequid Hills. Under similar climatic conditions, temperate hardwood species (e.g., red oak, beech) are projected to benefit from elevated GDD in the second (2011-2040) and third tri-decade (2041-2070), and experience some decline in the fourth tri-decade (2071- 2100). The report does not examine the impact of tree species currently south of NS as they move northward and begin to interact with tree species in the Acadian forest region of NS with climate warming.”

Worry about exotic forest pests and climate warming prompts talk about fertilizing deficient soils, reducing clearcuts and Assisted Range Expansion
Post, Sep 28, 2018. Could we add a dozen or so species to our hardwoods to better adapt to climate warming and increase resilience to pests?

Time to plan ahead: the future of the Acadian Forest in an era of climate warming
Post on this website Oct 29, 2017, highlighting a paper published in Forest Ecology and Management in September, 2017 titled Rapid 21st century climate change projected to shift composition and growth of Canada’s Acadian Forest Region by Anthony R Taylor of the Canadian Forestry Service and collaborators.

Silvicultural Discipline to Maintain Acadian Forest Resilience
Peter Salonius 2007. Northern Journal of Applied Forestry 24(2): 91- 97.
ABSTRACT: Clearcut harvesting decreases structural complexity, eliminates old and genetically superior legacy trees, extirpates mature-forest floor vegetation, and creates hot and dry postharvest microclimates. The short-lived, exposure-tolerant, boreal tree species that regenerate in large forest openings are believed to be less able, than the late-successional Acadian species they replace, to adapt to the climate warming expected during the next forest rotation. A strip silviculture design is presented that includes limited canopy opening, “no-traffic” areas, maintenance of “full-cycle” survivors, and programmed return harvest intervals that approximate natural gap disturbance as a means of arresting the further increase of boreal species and restoring Acadian species on the landscape. Within the confines of this silvicultural discipline, two management options are described to accommodate extremes of future energy availability.

Exploring adaptation to climate change in the forests of central Nova Scotia, Canada
James W.N. Steenberg et al. 2011 Forest Ecology and Management Volume 262, Issue 12, 15 December 2011, Pages 2316–2327.

Climate‐change vulnerability assessment for selected species in three national parks in eastern Canada
Takafumi Osawa, MES thesis, Dalhousie University 2015 “Canadian protected areas have been established with a premise of static distributionsof different ecosystems, an assumption invalidated by climate change. In the Maritimes, there are few local case studies on how to consider and manage protected areas with potentially vulnerable ecosystems. Assuming two climate-change scenarios in the 2080s, we conducted climate-change vulnerability assessments (CCVAs) for a range of species in three national parks as case studies in the face of climate change. Specifically, we had two main goals: (1) to conduct CCVAs, including NatureServe’s climate change vulnerability index, for terrestrial species in these areas, and (2) to explore adaptation opportunities. Our study then identified some of the most vulnerable species (e.g., American marten and brook trout) but also species that are adaptable to climate change. Identification of species’ vulnerability to a changing climate is the first step in trying to identify potential adaptation opportunities for these species.

NB Naturalist 44#3 (2017): Nature, Biodiversity and Climate Change
An edition NatureNB’s journal devoted climate change. Includes
Climate Change Impacts on Birds, P. W. Thomas, B. Whittam, G. Campbell; Invasive Species and Climate Change, D. Mazerolle; Shifting Trees, C. P.-A. Bourque; Storing Carbon, D. Prest and more referenced articles.

Changing Climate, Changing Forests: The Impacts of Climate Change on Forests of the Northeastern United States and Eastern Canada
Lindsey Rustad et al. 2011 U.S. Northern Research Station General Technical Report NRS-99
ABSTRACT Decades of study on climatic change and its direct and indirect effects on forest ecosystems provide important insights for forest science, management, and policy… Projections indicate significant declines in suitable habitat for spruce-fir forests and expansion of suitable habitat for oak-dominated forests. Productivity gains that might result from extended growing seasons and carbon dioxide and nitrogen fertilization may be offset by productivity losses associated with the disruption of species assemblages and concurrent stresses associated with potential increases in atmospheric deposition of pollutants, forest fragmentation, and nuisance species. Investigations of links to water and nutrient cycling suggest that changes in evapotranspiration, soil respiration, and mineralization rates could result in significant alterations of key ecosystem processes. Climate change affects the distribution and abundance of many wildlife species in the region through changes in habitat, food availability, thermal tolerances, species interactions such as competition, and susceptibility to parasites and disease. Birds are the most studied northeastern taxa. Twenty-seven of the 38 bird species for which we have adequate long-term records have expanded their ranges predominantly in a northward direction. There is some evidence to suggest that novel species, including pests and pathogens, may be more adept at adjusting to changing climatic conditions, enhancing their competitive ability relative to native species. With the accumulating evidence of climate change and its potential effects, forest stewardship efforts would benefit from integrating climate mitigation and adaptation options in conservation and management plans.

REDUCING GHG EMISSIONS//INCREASING CARBON SQUESTRATION

Accelerating the Coal Phase Out: Nova Scotia and the Climate Emergency
Prepared by Ralph Torrie, Torrie Smith Associates for the Ecology Action Centre, Nov 2019.”A technical report and modelling analysis of a low-carbon transition for Nova Scotia’s electricity and energy systems by 2030″

Green New Deal
We are a coalition of workers, artists, Indigenous leaders, scientists, youth, and people directly impacted by climate catastrophe — from cities and towns, businesses and communities, working beyond our political differences and in solidarity with Indigenous peoples — who want to ensure a safe world for our children and all generations after that.
https://act.greennewdealcanada.ca/town-halls/

Pannozzo on The Climate Emergency
The climate emergency: Why it’s time to ditch the language of economic growth
SEPTEMBER 26, 2019 BY LINDA PANNOZZO in the Halifax ExaminerThe Climate EmergencyPart 2: Why growth, even if it is green, is not enough
OCTOBER 11, 2019 BY LINDA PANNOZZO in the Halifax ExaminerTHE CLIMATE EMERGENCY: PART 3: HOW TO TURN OFF THE ECONOMIC GROWTH ENGINE
OCTOBER 24, 2019 BY LINDA PANNOZZO in the Halifax Examiner

The Climate Emergency: Part 4: Our current economy can’t address the crisis; what are we going to do about it?
NOVEMBER 8, 2019 BY LINDA PANNOZZO in the Halifax Examiner

XR Green New Deal Fact Sheet: Aiming for Net-Zero Emissions by 2025-2030
The Canadian Green New Deal’s objective to ‘half emissions by 2030’ is not sufficient to avoid catastrophic consequences.
We need to aim for ‘net-zero emissions by 2025-2030’ through rapid mobilization to repurpose our infrastructure to stay
within the safer 1.5°C target.

Negative Emissions Technologies and Reliable Sequestration: A Research Agenda.
National Academies of Sciences, Engineering, and Medicine. 2019 Washington, DC: The National Academies Press. doi: https://doi.org/10.17226/25259. 511 pages
Chapters Summary 1
1 Introduction 23
2 Coastal Blue Carbon 45
3 Terrestrial Carbon Removal and Sequestration 87
4 Bioenergy with Carbon Capture and Sequestration 137
5 Direct Air Capture 189
6 Carbon Mineralization of CO2 247
7 Sequestration of Supercritical CO2 in Deep Sedimentary
Geological Formations 319
8 Synthesis

Capturing carbon: Can it save us?
by Jeff Johnson, on C&EN, FEBRUARY 25, 2019 “We have technologies to remove greenhouse gases from air, but it’s less clear we can scale them fast enough to make a difference”

World’s forests increasingly taking up more carbon
February 25, 2019 by Cheryl Dybas, National Science Foundation on phys.otg
The world’s forests are increasingly taking up more carbon, partially offsetting the carbon being released by the burning of fossil fuels and by deforestation in the tropics, according to a new study.

Canada’s climate gap widens yet again
By Barry Saxifrage In National Observer, jan 30, 2019

Looking deeper: An investigation of soil carbon losses following harvesting from a managed northeastern red spruce (Picea rubens Sarg.) forest chronosequence
A. Diochon et al., 2009. Forest Ecology and Management 257:v413-420.
research conducted in Nova Scotia.”Storage of carbon reached a minimum 32 years post-harvest, at which time stores were approximately 50% of the intact forest. However, storage approached the range of the intact forest approximately 100 years post-harvest. ”

Are Protected Areas an Effective Way to Help Mitigate Climate Change? A Comparative Carbon Sequestration Model for Protected Areas and Forestry Management in Nova Scotia, Canada
By Robert Cameron and Peter Bush, 2016. The International Journal of Interdisciplinary Environmental Studies 11: 2329-1621. ABSTRACT Abstract: Protected areas have been proposed as a tool for mitigating climate change through carbon storage and sequestration. A C forest model was developed using carbon yield curves from the US Forest Service. The model was run on existing protected areas comprising 514,000 ha and 245,000 ha of proposed protected areas in Nova Scotia, Canada under three scenarios: 1. complete protected status; 2. forestry management which maximized timber yield; and 3. forestry management with environmental considerations. The model suggested 112 million tonnes of C is stored in existing and proposed protected areas and if protected these forests would sequester C over the next 130 years. If the proposed and existing protected areas were managed for forestry they would become a C source for the next 130 years for both maximum yield and forestry management with environmental considerations scenarios. There was a decrease of about 2 percent and 11 percent in total amount of C stored for forestry management with environmental considerations and maximum yield scenarios respectively. Frequent disturbance from clear-cut harvesting likely increases decomposition of organic matter in the forest which exceeds C sequestration by regrowth. The greatest advantage of protected areas is the greater certainty in land use and in maintaining the current and future C store.

“We cannot log and burn our way out of climate change”
Post on this website Mar 22, 2017. So says Dr. Bill Moomaw, Professor of International Environmental Policy at Tufts University and an author of The Great American Stand: US Forests & The Climate Emergency. “Logging forests and burning trees to generate electricity in place of coal while not counting the emissions may help governments meet their emission goals, but the atmosphere and climate is where the real accounting takes place.” View The Great American Stand: US Forests & The Climate Emergency by Bill Moomaw and Danna Smith, Dogwood Alliance Media Release, Mar 21, 2017.

Natural Resources Canada GHG Calculator confirms Nova Scotia forest bioenergy schemes are worse than coal
Post on this website, Jan 3, 2017. The common assumption that forest bioenergy schemes involving harvest of living trees are carbon neutral was seriously challenged in 2009 when a group of U.S. Scientists published a paper in the prestigious journal Science titled Fixing a Critical Climate Accounting Error. There has been a plethora of evidence produced both before and since that paper challenging the carbon-neutral assumption.

Granite Geek: Burning wood for power makes sense – or so I thought
Concord Monitor Sep 26, 2017 “It’s no fun to realize that you’ve been wrong, so this isn’t a fun column. For years I’ve supported the idea that whenever possible, Northern New England should swap fossil-fuel power and heat for wood-fired power, taking advantage of our tree-laden status as the “Saudi Arabia of biomass” to boost the logging industry while also doing environmental good. It’s a pretty obvious position. But over the years I’ve come to realize that surprisingly often, this isn’t a good idea from the environmental point of view. Quite the opposite.”

Greenhouse gas emissions of local wood pellet heat from northeastern US forests
Thomas Buchholz, John S. Gunn, David S. Saah. , Energy (2017), doi: 10.1016/j.energy.2017.09.062. View Accepted manuscript pdf
ABSTRACT: We explored greenhouse gas (GHG) implications of locally-sourced and produced wood pellets to heat homes in the US Northern Forest region… An industry-average pellet feedstock mix (50% sawmill residues, 50% pulpwood) appeared to generate heat that was at least at parity with fossil-fuel heating alternatives when harvest levels remain unchanged due to pellet production. If harvest levels increase due to pellet production, using pellet heat increased GHG emissions. If baseline harvest levels drop (e.g., following the loss of low-grade markets), GHG emissions from pellet heat would at least remain stable relative to fossil alternatives.

Timber is Oregon’s biggest carbon polluter
Carl Segerstrom HIGH COUNTRY NEWS May 16, 2018. ” the study Law and her colleagues put together earlier this year found that wildfire is not the biggest source of climate-warming carbon dioxide in Oregon forests — logging and wood products are.”

Medway Community Forest Co-op: A Summary of the Crown and Carbon Report
Mary Jane Rodger, June 5, 2018 “This past winter the Medway Community Forest commissioned a report done by several Master’s students from the Dalhousie Management Without Borders class to determine an effective policy model for the sale and management of carbon credits from MCFC lands.”

Earth’s intact forests vanishing at accelerating pace: Scientists
On www.straitstimes.com, Jun 21, 2018:”…Many forest-products carry the FSC label, designed to reassure eco-conscious consumers.
But approximately half of all intact forest landscapes inside FSC-certified concessions were lost from 2000 to 2016 in Gabon and the Republic of Congo, the new data showed…National and regional parks have helped to slow the rate of decline. The chances of forest loss was found to be three times higher outside protected areas than inside them, the researchers reported.”

Where humanity first caused lasting environmental change: new study
Melanie Green for www.thestar.com, Jun 13, 2018. Ancient agricultural activity more than 2,000 years ago is the tipping point where humanity first began to cause environmental change, according to a new study. The findings — discovered by a team of international researchers led by the University of British Columbia — point to increased intensity of deforestation and farming practices during the Bronze Age in Ireland. This affected the world’s nitrogen cycle, which is a process that keeps the essential element circulating between the atmosphere, land and oceans.

VIBERT: Yup, a price on carbon costs money
Jim Vibert in the Chronicle Herald, July 4, 2018 “What part of the phrase “a price on carbon” don’t people understand?
From the time anyone bothered to pay him any heed, Justin Trudeau has said there will be a price — or because it is government-imposed, a tax — on producing carbon emissions in Canada. That price by 2022 is supposed to be equivalent to $50 per tonne. A University of Calgary economics professor has done a bunch of calculations and come up with a scary bill of $1,120 a year for an average Nova Scotian family. Ouch. But it’s also a tad frightening that a typical Nova Scotian household accounts for more than 22 tonnes of the crud annually. The provincial government likes to say Nova Scotia has already done its part in reducing carbon emissions, which is true, sort of. Nova Scotia has been an early leader in cutting carbon emissions but also had a longer way to go than most other provinces…”

NEK forestland conserved as Vermont goes into the carbon storage business
By Elizabeth Gribkoff on vtdigger.org/, July 12, 2018 “Burnt Mountain, a 2,800-foot-high point on a forested ridge in the Northeast Kingdom, will be conserved as a wild area by The Nature Conservancy. It will be the state’s first carbon storage project to enroll in California’s cap and trade program, the conservancy announced Thursday.”

Scientists champion forests as ‘unsung hero’ of climate action
by Megan Rowling for Thomson Reuters Foundation News, Oct 5, 2018. Cites the statement Five Reasons the Earth’s Climate Depends on Forests.

CLIMATE CHANGE DYNAMICS

A Cold Case Turns Hot
The Potsdam Institute for Climate Impact Research 2017. Pamphlet provides a historical overview of scientific thinking about climate change.

Avoid Gulf stream disruption at all costs, scientists warn
The Guardian, Apr 13, 2018. “How close the world is to a catastrophic collapse of giant ocean currents is unknown, making halting global warming more critical than ever, scientists say”

Tipping Elements – the Achilles Heels of the Earth System
“Tipping elements are components of the Earth system of supra-regional scale which – in terms of background climate – are characterized by a threshold behavior. Once operating near a threshold, these components can be tipped into a qualitatively different state by small external perturbations. To compare them with the human body, tipping elements could be described as organs which drastically alter or stop their usual function if certain requirements, such as oxygen supply, are not sufficiently fulfilled.
The threshold behavior is often based on self-reinforcing processes which, once tipped, can continue without further forcing. It is thus possible that the new state of a tipping element persists, even if the background climate falls back behind the threshold. The transition resulting from the exceedance of a system-specific tipping point can be either abrupt or gradual. Its large-scale environmental impacts could endanger the livelihood of millions of people.”

Map of the most important tipping elements in the Earth System overlain on the Köppen climate classification. There are three groups of tipping elements: melting ice bodies, changing circulations of the ocean and atmosphere, and threatened large-scale ecosystems. Question marks indicate systems whose status as tipping elements is particularly uncertain. SOURCE: www.pik-potsdam.de

Related: The Earth is in a death spiral. It will take radical action to save us
George Monbiot, Opinion in The Guardian Nov 14, 2018

How much wood should a wood-cutter cut?
By Nelson Bennett | November 8, 2018 Declares Werner Kurz, senior research scientist at Natural Resources Canada’s Canadian Forest Service:

“Conservationists argue that old mature forests should not be logged because they store such huge amounts of carbon. Others argue that, as long as the carbon remains sequestered in products like lumber, and as long as the trees are replanted, a younger working forest takes up more CO2 than a mature intact forest”

“One of the things that is absolutely clear is that an old forest with big trees contains, at the moment, more carbon than a young forest,” Kurz said. “But the young forest is more actively growing and removes more carbon from the atmosphere than the old forest.

“This is the part where there’s some debate. But the science clearly indicates that old forests are much weaker carbon sinks than young forests. And old forests tend to be more susceptible to insects, to drought, to fires, etcetera.

“That doesn’t mean we need to convert all forests into young forests. There are many reasons why we want to preserve old forests – as carbon stores, for biodiversity, for ecosystem resilience. But the argument that we preserve old forests to maintain a carbon sink is not a valid one.”

I find it hard to understand how removing a huge carbon store in OG forest and replacing it with a newly growing trees, while putting some of the wood into products with an average life expectancy of ? 50 years ? could reduce CO2 emissions over a meaningful time-frame… I will try to get a response from Kurz about it. – dp Nov 12, 2018.

Contrary to common belief, some forests get more fire-resistant with age
On theconversation.com, Apr 4, 2018

Natural climate solutions for the United States
Joseph E. Fargione et al., Science Advances, 14 Nov 2018: Vol. 4, no. 11, eaat1869 DOI: 10.1126/sciadv.aat1869 “Limiting climate warming to <2°C requires increased mitigation efforts, including land stewardship, whose potential in the United States is poorly understood. We quantified the potential of natural climate solutions (NCS)—21 conservation, restoration, and improved land management interventions on natural and agricultural lands—to increase carbon storage and avoid greenhouse gas emissions in the United States. We found a maximum potential of 1.2 (0.9 to 1.6) Pg CO2e year−1, the equivalent of 21% of current net annual emissions of the United States. At current carbon market prices (USD 10 per Mg CO2e), 299 Tg CO2e year−1 could be achieved. NCS would also provide air and water filtration, flood control, soil health, wildlife habitat, and climate resilience benefits.”

How Extreme Weather Is Shrinking the Planet
Bill McKibben in the New Yorker, Nov 26, 2018. With wildfires, heat waves, and rising sea levels, large tracts of the earth are at risk of becoming uninhabitable. But the fossil-fuel industry continues its assault on the facts.

A global map to understand changing forests
by Brian Wallheimer, Purdue University for Phys.org May 16, 2019. “The Global Forest Biodiversity Initiative developed the first map of global tree symbioses. The map will help answer questions about environmental impacts associated with forest changes, forest management and biological conservation” Cites Climatic controls of decomposition drive the global biogeography of forest-tree symbioses by B. S. Steidinger et al., Nature volume 569, pages 404–408 (2019). “The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools1,2, sequester carbon3,4 and withstand the effects of climate change. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems.”

Tall and old or dense and young: Which kind of forest is better for the climate?
By Paul Koberstein & Jessica Applegate, Mongabay.com . May 27, 2019

CARBON FO0TPRINT

Calculate and offset your CO2 emissions!
It really is surprising how much CO2 emissions we produce in everyday life. For instance, CO2 and other emissions are caused when driving a car, heating a house, cooking, working, celebrating or flying. These CO2 emissions can easily be calculated with the myclimate carbon footprint calculators and then offset in myclimate carbon offset projects.