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State of the climate: Heat across Earth’s surface and oceans mark early 2019

Posted on 6 June 2019 by Zeke Hausfather

This is a re-post from Carbon Brief

Global surface temperatures in 2019 are on track to be either the second or third warmest since records began in the mid-1800s, behind only 2016 and possibly 2017.

On top of the long-term  warming trend, temperatures in 2019 have been buoyed by a moderate El Niño event that is likely to persist through the rest of the year.

That’s one of the key findings from Carbon Brief’s latest “state of the climate” report, a quarterly series on global climate data that now includes temperatures, ocean heat, sea levels, greenhouse gas concentrations, climate model performance and polar ice.

Ocean heat content (OHC) set a new record in early 2019, with more warmth in the oceans than at any time since OHC records began in 1940.

The latest data shows that the level of the world’s oceans continued to rise in 2019, with sea levels around 8.5 centimetres (cm) higher than in the early 1990s.

Atmospheric methane concentrations have increased at an accelerating rate, reaching record highs in recent months, though scientists are divided on the cause of this trend.

Arctic sea ice is currently at a record low for this time of year. Antarctic sea ice set new record lows in January, and is currently at the low end of the historical range.

Third warmest start to a year

Global surface temperatures are recorded and reported by a number of different international groups, including NASANOAAMet Office Hadley Centre/UEABerkeley Earth and Cowtan and WayCopernicus/ECMWF also produces a surface temperature estimate based on a combination of measurements and a weather model – an approach known as “reanalysis”.

The chart below compares the annual global surface temperatures from these different groups since 1970 – or 1979 in the case of Copernicus/ECMWF. The coloured lines show the temperature for each year, while the dots on the right-hand side show the year-to-date estimate for January through March 2019. Values are shown relative to a common baseline period, the 1981-2010 average temperature for each series. Surface temperature records have shown around 0.86C warming since the year 1970, a warming rate of about 0.19C per decade.

Year-to-date values are only shown for NASA, NOAA, and Copernicus as data for March is not yet available from the UK Hadley Centre, which also prevents the Berkeley Earth and Cowtan and Way records from being released. The year-to-date values in this chart will be updated when that data becomes available.

Annual global mean surface temperatures from NASA GISTEMPNOAA GlobalTempHadley/UEA HadCRUT4Berkeley EarthCowtan and Way and Copernicus/ECMWF (lines), along with 2019 temperatures to-date (January-March, coloured dots). Anomalies plotted with respect to a 1981-2010 baseline. Chart by Carbon Brief using Highcharts.

Based on temperatures in the first quarter, 2019 is likely to be the second or third warmest year on record for all of the surface temperature series. However, with only three months of 2019 available so far it is not out of the question that it could be the warmest year – or as cool as the fourth warmest on record.

The figure below shows how temperatures to-date compare to prior years in the NASA GISTEMP dataset (using its new version 4). It shows the temperature of the year-to-date for each month of the year, from January through the full annual average.

Year-to-date temperatures for each month from 2012 to 2019 from NASA GISTemp. Anomalies plotted with respect to a 1981-2010 baseline. Chart by Carbon Brief using Highcharts.

In the NASA dataset, 2019 has had the third warmest January-March average on record, after the record warm years of 2016 and 2017. However, while both of those years had cooler temperatures in the summer and autumn, this year may see a weak El Niño help current warmth persist. As a result, it is likely that 2019 will end up as the second warmest on record in the NASA dataset.

The first three months of 2019 have already been modestly warmed by a weak El Niño event. The majority of forecast models expect weak El Niño conditions to persist for the remainder of 2019, with sea surface temperatures in the tropical Pacific around between 0.5C and 1C above the recent average.

El Niño and La Niña events – collectively referred to as the El Niño Southern Oscillation, or ENSO – are the main driver of year-to-year variation on top of the long-term surface warming trend. ENSO events are characterised by fluctuations in temperature between the ocean and atmosphere in the tropical Pacific, which help to make some years warmer and some cooler.

The figure below shows a range of ENSO forecast models produced by different scientific groups, with the average for each type of models shown by thick red, blue and green lines. Positive values above 0.5C reflect El Niño conditions, while negative values below -0.5 reflect La Niña conditions.

El Niño Southern Oscillation (ENSO) forecast models for three-month periods in the Niño3.4 region (February, March, April – FMA – and so on), taken from the CPC/IRI ENSO forecast.

El Niño Southern Oscillation (ENSO) forecast models for three-month periods in the Niño3.4 region (February, March, April – FMA – and so on), taken from the CPC/IRI ENSO forecast.

In general, El Niño periods tend to be warmer than other months, with the large warm patch in the tropical east Pacific transferring extra heat to the atmosphere. Similarly, La Niña events cool global temperatures. In both cases the effects tend to have a bit of a lag: the effect on global temperatures is small at the beginning of the event, and larger by the end – or slightly after.

Comparing climate models with observations

Climate models provide physics-based estimates of future warming given different assumptions about future emissions, greenhouse gas concentrations and other climate-influencing factors.

Model estimates of temperatures prior to 2005 are a “hindcast” using known past climate influences, while temperatures projected after 2005 are a “forecast” based on an estimate of how things might change.

The figure below shows the range of individual models forecasts featured in the IPCC fifth assessment report – known collectively as the CMIP5 models – between 1970 and 2020 with grey shading and the average projection across all the models shown in black. Individual observational temperature records are represented by coloured lines.

Annual global average surface temperatures from CMIP5 models and observations between 1970 and 2020. Models use RCP4.5 forcings after 2005. They include sea surface temperatures over oceans and surface air temperatures over land to match what is measured by observations. Anomalies plotted with respect to a 1970-2000 baseline. Chart by Carbon Brief using Highcharts.

While global temperatures were running a bit below the pace of warming projected by climate models between 2005 and 2014, the last few years have been pretty close to the model average. This is particularly true for globally-complete temperature records such as NASA, Berkeley Earth and the Copernicus reanalysis that include temperature estimates for the full arctic. Temperatures were warmer than the multimodel average during the 2015-16 super-El Niño event and were a bit cooler during the 2018 La Niña. In recent months, temperatures have been ticking back upward.

Ocean heat content at a record high

Human-emitted greenhouse gases trap extra heat in the atmosphere. While some of this warms the Earth’s surface, the vast majority – upwards of 90% – goes into the oceans. Most of this accumulates in the top 700 metres, but some is also mixed into the deep oceans.

Ocean heat content (OHC) estimates between 1940 and the present day for both the upper 700m (light blue shading) and 700m-2000m (dark blue) depths of the ocean are shown in the chart below.

Monthly global ocean heat content (in zettajoules – billion trillion joules, or 10^21 joules) for the 0-700 metre and 700-2000 metre layers. Data from Cheng et al 2017, updated through March 2019. Chart by Carbon Brief using Highcharts.

The first few months of 2019 have set new records for OHC, with a particularly pronounced jump in February and March 2019. Dr Lijing Cheng, an associate professor at the Institute of Atmospheric Physics in China and the lead researcher on the OHC dataset, tells Carbon Brief that the unusual jump was concentrated “below 300m at around 40N in the Atlantic Ocean”. He cautions against drawing conclusions from the last two months until researchers have had time to investigate and make sure the data is accurate.

In many ways, OHC represents a much better measure of climate change than global average surface temperatures. It is where most of the extra heat ends up and is much less variable on a year-to-year basis than surface temperatures. Most years set a new record for OHC and 2019 has been no exception so far, with the first three months showing the warmest OHC since records began.

Changes in the amount or rate of warming are much easier to detect in the OHC record than on the surface. For example, OHC shows little evidence of the slowdown in warming in the mid-2000s, seen in surface temperature records. It also shows a distinct acceleration after 1991, matching the increased rate of greenhouse gas emissions over the past few decades.

Sea level rise continues

Modern-day sea levels rose to a new high in 2019 to-date, due to a combination of melting land ice – glaciers and ice sheets – and the thermal expansion of water as it warms.

The figure below shows the increase in global sea level since it was first measured by satellites in the early 1990s. The different coloured lines indicate different satellite missions over the years. Earlier sea level data from tide gauges is also available, with data going back to the late 1800s.

Global average sea level based on satellite data from January 1993 to present from NOAA. A correction for global average isostatic rebound of 0.3mm/yr is added.

Sea level rise is sensitive to global surface temperatures; El Niño years where temperatures are a bit warmer tend to have more rapid sea level rise than La Niña years. For example, sea level increased rapidly from 2014 to 2016. However, these are relatively small fluctuations around the consistent long-term trend. Overall sea levels have risen around 8.5cm since the early 1990s, and around 22cm since the 1880s.

Sea level data is corrected for glacial isostatic adjustment –  the rebound of the Earth from the several kilometre-thick ice sheets that covered much of North America and Europe around 20,000 years ago. This adjustment is relatively small, only adding around 0.3mm/yr to sea level rise rates, or around 10% of the current rate of sea level rise.

Rapid rise in atmospheric methane

While CO2 is by far the largest factor in rising global temperatures – accounting for roughly 50% of the increase in “radiative forcing” since the year 1750 – methane is the second most important, accounting for for 29% of the increase in forcing.

Atmospheric methane concentration increased rapidly from the mid-1980s through to the early 1990s, before slowing down and ultimately pausing in the late 1990s and 2000s. However, starting in 2008, levels of atmospheric methane begane growing again and have seen a notable acceleration over the past four years. The chart below shows concentrations of methane – in parts per billion (ppb) – from the early 1980s when global measurements were first available through to the present.

Global concentrations of methane based on data from NOAA’s Earth Systems Research Laboratory. Chart by Carbon Brief using Highcharts.

The cause of the increase in methane concentrations over the last decade is still a subject of scientific debate. Some studies have suggested that wetlands and rice cultivation in the tropics are the primary culprit and that the expansion of unconventional oil and gas extraction plays a limited role. Others argue that fossil fuels have had just as important a role in the increase as agriculture.

Unlike CO2, methane has a relatively short lifetime in the atmosphere, only lasting about nine years on average before breaking down into its component parts. This means that while CO2 keeps accumulating even if emissions remain flat, the amount of methane in the atmosphere is directly related to the rate of emissions. This means that increases in atmospheric concentrations in recent years reflect increases in methane emissions.

Arctic sea ice at record low

Arctic sea ice spent much of early 2019 at the low end of the historical range and has fallen to record lows for this time of year during the past month. Antarctic sea ice hit record lows in early January, though it has since recovered a bit. Both the Arctic sea ice winter maximum and Antarctic summer minimum in 2019 were the seventh smallest in their respective satellite records.

The figure below shows both Arctic and Antarctic sea ice extent in 2019 (solid red and blue lines), the historical range in the record between 1979 and 2010 (shaded areas) and the record lows (dotted black line). Unlike global temperature records, sea ice data is collected and updated on a daily basis, allowing sea ice extent to be viewed through to the present.

Arctic and Antarctic daily sea ice extent from the US National Snow and Ice Data Center. The bold lines show daily 2019 values, the shaded area indicates the two standard deviation range in historical values between 1979 and 2010. The dotted black lines show the record lows for each pole. Chart by Carbon Brief using Highcharts.

The chart below shows the average Arctic sea ice extent for each week of the year for every year between 1978 and 2019. (Prior to 1978, satellite measurements of sea ice extent are not available and the data is much less reliable.)

Arctic and Antarctic weekly sea ice extent from the US National Snow and Ice Data Center from 1979 through April 2019.

The figure shows a clear and steady decline in Arctic sea ice since the late 1970s, with darker colours (earlier years) at the top and lighter colors (more recent years) much lower. A typical summer now has nearly half as much sea ice in the Arctic as it had in the 1970s and 1980s, though 2012 still holds the record for the lowest summer minimum sea ice extent.

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Comments 1 to 27:

  1. A related important data set is the atmospheric CO2 concentration values.

    The presentations of information for CO2 compiled by NOAA include the following about the "Annual Mean Global Carbon Dioxide Growth Rates".

    What is glaringly obvious, and cause for concern, is that the growth rates since 2011 have exceeded 2.0 ppm. In the set of earlier years there were some years over 2.0 ppm growth. But they were interspersed with rates well below 2.0 ppm growth.

    So far in 2019 the average of CO2 monthly increases also exceeds 2.0 ppm.

    I wonder of the 'Business as Usual' case that is often talked about needs to be updated to reflect the reality that 'Increase of Harmful Business has been Becoming More Usual'. That update would result in even higher temperature increases in the nearer and distant future due to more rapidly increased CO2 levels than the apparently outdated 'Business as Usual' case.

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  2. OPOF, that CO2 chart is very illuminating, and yes  yearly atmospheric C02 growth rates typically increased after 2011. If you look at trends of emissions they underwent an obvious increase in the rate after 2000 due to an increase in use of oil and coal here, (in Asia I think) so presumably the increase in the yearly rate of atmospheric growth rates from 2011 is a delayed response to this?

    Although yearly rate of atmospheric growth rates changed after 2011, If you take the years 2012 - 2018, and adjust 2015 and 2016 down to say 2.4 to reflect the fact they were in the middle of a big el nino (just a guesstimate on my part), then the trend across the whole period is about 2.2 on average, and fairly flat looking. So this might be a good sign that rates of use of fossil fuels are at least not accelerating since 2012, so far anyway.

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  3. To say the increase in concentration is flat means the rate of increase is not accelerating.  In my own effort to project future concentrations with business as usual (2ppm/year), the concentration still rises, even if the rate of increase remains flat.  This reminds me of the debate about US government debt.  If the rate of the increase was in decline, they would say the annual deficit was declining, even though the accumulative debt was still rising. For a short time in 2000, the US actually had a surplus.  However, the overall accumulated debt did not go down.  It was still there.  That is why I promote using financial metaphor for considering CO2 concentration in the atmosphere.  When emissions (expenses) exceed income (sequestration) the difference is made up with loans (debts).  The annual imbalance between emissions and sequestrations determine if atmospheric concentrations go up or down.  The ONLY way to lower concentration is to reduce emissions below the amount that can be sequestered with the difference subtracted from atmospheric concentration (payment on debt).  Sequestration (Income) can be increased by reforestation and possibly geoengineering.  Although the net sequestration by nature will likely be our primary income for a long time.  When people recognize net emissions as a debt, they will recognize the need to repay the debt by reducing emission to less than what can be sequestered.  Treating emissions as free and unlimited in the econmy is leading us to a violent outcome.  

    Graphs above looked very interesting.  Unfortunately, in my Chrome browser, I could not see the whole graph in a single image, requiring scrolling to see the scales.  This made them difficult to read.  Please consider displaying whole graph as single image.  Otherwise, the info on the website is very much appreciated.  

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  4. @3. ELIofVA,

    I love the way you have set this up in a way that parallels economics. I strongly believe this is indeed the way to think about carbon and AGW! It took me a while to think of the problem in this way too, years ago. But once I did then it helped clarify my thought processes. I even took a university course on AGW to learn the proper jargon so I could communicate with climate scientists. As it turns out agricultural and soil science uses a different set of technical jargon than climate scientists which use a different set than economists! However, the thought process of all three are often parallel and only differ in terminology.

    There is one big flaw in your post though. You are thinking about the problem correctly but got your key terrestrial biome wrong. It is the  grasslands rather than the forests that are the key component to cooling the planet.

    Cenozoic Expansion of Grasslands and Climatic Cooling

    I would hate to see such a high quality way of approaching AGW mitigation fail simply because the wrong ecosystems were used. And not just that, but the wrong part of the carbon cycle itself. 

    So yes, I am behind you 100%. But the trick is the soil, not biomass. This means trees can help but they are not enough. They would reach biomass saturation long before actually reducing CO2 ppm in the atmosphere low enough to stop AGW. They could reduce the increase for a short while, but they are not a long term solution at all.

    On the other hand grassland restoration does not have this limitation because grasslands sequester CO2 differently both short term and long term.

    Right from the beginning grasslands start sequestering more CO2 because the C4 pathway is more efficient and productive than the C3 pathway.

    C4 carbon fixation - Wikipedia

    C4 metabolism originated when grasses migrated from the shady forest undercanopy to more open environments, where the high sunlight gave it an advantage over the C3 pathway.

    … Today, C4 plants represent about 5% of Earth's plant biomass and 3% of its known plant species. Despite this scarcity, they account for about 23% of terrestrial carbon fixation. Increasing the proportion of C4 plants on earth could assist biosequestration of CO2 and represent an important climate change avoidance strategy.

    But there is more to it than just the initial growth phase. Because grasslands also reach biomass saturation faster than forests too. What happens then is a little known and just recently discovered symbiosis between grasses and mycorrhizal fungi in the soil. It all started with a USDA soil scientist named Dr. Sara F. Wright and her discovery in 1996 of a glycoprotein produced abundantly on hyphae and spores of arbuscular mycorrhizal fungi (AMF) in soil, called Glomalin.

    Glomalin eluded detection until 1996 because, “It requires an unusual effort to dislodge glomalin for study: a bath in citrate combined with heating at 250 F (121 C) for at least an hour.... No other soil glue found to date required anything as drastic as this.” - Sara Wright.

    This was no small discovery, as it turns out that this glomalin producing, highly evolved, mutualistic, symbiotic relationship found between AMF and plants is the most prevalent plant symbiosis known, being found in 80% of vascular plant families in existence today. Dr. Wright had discovered the link between photosynthesis and fully 1/3 of the stored soil carbon.

    Glomalin: Hiding Place for a Third of the World's Stored Soil Carbon

    But it gets even better. Turns out that being a soil glue like substance, it also locks into the soil other organic substances, holding even more carbon.

    Glomalin is Key to Locking up Soil Carbon

    Glomalin: The Real Soil Builder

    Glomalin, the Unsung Hero of Carbon Storage

    Liquid carbon pathway unrecognised

    Little Known Glomalin, a Key Protein in Soils

    In other words it’s not just the glomalin itself, but rather this is just the missing link in a more extensive biochemical pathway that is an anabolic process, unlike the more well known decomposition of organic matter which is a catabolic process releasing CO2. It has long puzzled soil scientists how the processes of decay could actually at some point stop decaying into smaller and simpler humic substances, then begin to build larger and more complex stable carbon polymers and structures found in building new topsoil. There is still a lot to be researched, but we have found that pathway! The anabolic processes start with AMF which uses those root exudates to provide the energy to combine glomalin with products of decay as building blocks for the stable carbon soil creation process.

    Remember too, once biomass saturation is reached an increasingly higher % of the products of photosynthesis are pumped into the soil via this newly discovered liquid carbon pathway (LCP).

    Carbon sequestered deep in the soil profile has 3 main advantages over biomass carbon.

    1. It is safe from forest fires and grass fires. Fires send the biomass carbon right back into the atmosphere. Little if any long term sequestration.
    2. The soil sink size is larger than all the atmospheric CO2 and biomass CO2 combined. There simply isn’t enough atmospheric CO2 to saturate the soil sink. It’s that large.
    3. We have to repair our degraded soils anyway so that agriculture can continue. So it kills 2 birds with one stone. SOS: Save our Soils Dr. Christine Jones Explains the Life-Giving Link Between Carbon and Healthy Topsoil

    Since we really do have to do it anyway and soon, there really is no excuse.

    Only 60 Years of Farming Left If Soil Degradation Continues

    There is no free lunch. So yes, we still need solar energy, windmills, nuclear where appropriate and safe, hydroelectric and geothermal just to name a few. However, we certainly do not need to eliminate fossil fuels completely, just use them more wisely.

    Executive summary:

    Yes we can reverse Global Warming.

    It does not require huge tax increases or expensive untested risky technologies.

    It will require a three pronged approach worldwide.

    1. Reduce fossil fuel use by replacing energy needs with as many feasible renewables as current technology allows.
    2. Change Agricultural methods to high yielding regenerative models of production made possible by recent biological & agricultural science advancements.
    3. Large scale ecosystem recovery projects similar to the Loess Plateau project, National Parks like Yellowstone etc. where appropriate and applicable. So yes a few trees can help here.
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  5. RedBaron:

    Getting the economic indicators to encourage the solution is key.  I would modify my above statement, "The only way to reduce atmospheric concentration is to reduces emissions from all sources to less than what can be sequestered from all sources (natural and human influenced).  Pricing carbon is the best way to motivate the economy.  I want to pay farmers for acieving net sequestration from activities such as reforesting as well as increasing carbon content in their soils.  Before any of these kinds of policies can be successful, their needs to be broad recognition in the public of this demand by nature.  

    In your discussion of the potential to store carbon in soils of grasslands, does this apply to areas that are naturally forest.  In my area of Virginia, grasslands (pastures and hayfields) only exist to serve an animal ag which is commonly sited for high emissions.  Do  you see a pathway to achieve net sequestration in grasslands to cover these other emissions?  My intuition is that your claimes mainly apply to areas where grassland is natural such as in the Great Plains of US and Canada.  I am studying your point that soil has enormous potential as a carbon sink.  The other question is how permanent the storage.  Is the Globulin you describe permanent?  I am an advocate for biochar because it is permanently sequestered carbon as opposed to biologically active organic material that holds carbon until it decomposes.  In a healthy soil, the bio diversity captures those emissions in other biology preventing emission to the atmosphere.  One theory about the Great Plains is that periodic natural fires created over long times charcoal giving it the black soil that holds biologicaly active carbon giving it fertility.  

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  6. @ELIofVA,

    You asked if it includes natural forest areas like your home in VA. The answer is that it includes the open woodland/ savanna biomes that have a grassland understory but not the closed canopy forests.

    This includes the other properties too. For example the grassland biome is also a net sink for methane, but a closed canopy forest is a net source for methane. However, the open woodland/ savanna is a net sink just like the open prairie.

    Your claim that there were no native grasslands in Virginia is demonstrably false. Indeed the whole Shenandoah valley contained many grassland biomes from from the well-known Big Meadows to smaller areas along stream banks and every changing and evolving successional states scattered throughout. Deer and bison are indeed native species to Virginia that only feed on low vegetation and are not found in closed canopy mature forest. And once before human impact, there were also mastodons who like elephants are an ecosystem engineer keeping vast areas in continual renewal by removing trees and brush.

    The ability to sequester carbon in large quantities is capable anywhere we do agriculture now + an addition bit in areas too degraded for agriculture now, but that were at one time capable of supporting a productive grassland before becomeing desertified by mankind.

    Biochar is certainly useful and I have done some trials with it too. It is much smaller than the LCP but in fact the "bio diversity" in healthy soil that biochar promotes includes AMF so I do see it as useful together.

    You said, "One theory about the Great Plains is that periodic natural fires created over long times charcoal giving it the black soil that holds biologicaly active carbon giving it fertility."

    Yes what you are refering to as "black soil" is actually a mollisol. There have been many theories about where that molic epipedon came from including the fire one you mentioned. None of the older theories quite added up though.

    The mollic epipedon is a key diagnostic epipedon in Soil Taxonomy (Soil Survey Staff 2010) and is recognized in many other soil classification schemes as black soil, Chernozems, chestnut soils, Brunizems, Phaeozems, and Kastanozems. The origin of the mollic epipedon is only partially understood; however, the relation between Mollisols and grassland or steppe has been recognized for more than a century (Shantz 1923). Soils containing a mollic epipedon are among the world’s most productive soils (Liu et al. 2012). The thickness and high soil organic carbon (SOC) contents of the mollic epipedon mean that these soils have sequestered large amounts of C over long periods of time. Mollic Epipedon

    Now we know what can sequester enough carbon to have made this vast mollic epipedon. It is indeed the glomalin producing EMF found in symbiosis with grasses, especially C4 grasses mixed with other grasses and forbs. In other words the vast prairies and also the savannas and open woodlands of temporate areas containing understory grasses.

    Fire certainly was a part of grasslands biomes especially when animals for some reason were too low in number to keep up with recycling the huge biomass produced annually. However, most that carbon gets returned to the atmosphere rather than creating new soil. We now know that theory was wrong and the black soils were mainly created by the LCP.

    Oh and BTW Glomalin itself is not permanent, although very stable with a 7-42 year 1/2 life in the top A horizons, and up to a 300 year 1/2 life in the deeper B horizons. However, the key difference is that when it finally does decay, it forms humic polymers that tightly bind to the soil mineral substrate instead of decomposing to CO2. (creates the mollic epipedon mentioned above) So while glomalin is not permanent, a high % (~78% iirc) of its carbon is sequestered into deep geological timeframes. (unless we disturb that land with the plow and agrochemicals)

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  7. RedBaron

    In grassland do you know what is the balance between the cattle emission and the sequestration of carbon. Methane is stil a minor greenhose gas as far as effect is concerned and is of short lifetime.

    Traditional cropping of wheat etc is known to cause erosion of soils and so loss of carbon capture potental and possibly a worse option than pastoralism. We have bean counters that only look at the emissions in agriculture and do not take in the whole picture - whichI suspect no one as yet knows

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  8. @7 barry,

    I wrote this to help people understand Methane fuxes and how it relates to agriculture.

    What reaction can you do to remove methane?

    And I wrote this to take in the whole picture, including crop production and animal husbandry for ever major food system on the planet. There are a few minor gaps, but all the major food sources are covered worldwide.

    Can we reverse global warming?

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  9. RedBaron. I am familiar with EliofVA's treatment of emissions in the form of an economic perspective...we are personally acquainted. I am familiar with the role of A Miccorhizae's symbiosis with plants and it's participation in carbon sequestration, but I don't get the points about c3 and c4 grasses nor the subordination of trees-to-grass as a less carbon effective sequesterer...I hope I'm making sense, here...Also, what is the proportional value of phytoplankton in this "sequestration" activity? And what is the impact of the recent news that some 40% of phytoplankton have disappeared from the world's oceans since 1952?

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  10. RedBaron

    One more thing...are you taking the position that animals grazing the Great Plains helped create the soil there ? 

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  11. @swampfoxh,

    You asked, "I don't get the points about c3 and c4 grasses nor the subordination of trees-to-grass as a less carbon effective sequesterer"

    Most trees and some grasses are C3. but warm season grasses are C4. Since the C4 pathway is at least 5-10 times more efficient at photosynthesis, those plants primary productivity of products of photosynthesis start out many times greater baring other limiting factors. One of the main limiting factors in temporate grasslands is winter. So the solution that evolution came up with is a biodiverse mix of C4 and C3 grasses and forbs that each have a season they are dormant and a season they become dominant or co-dominant. This extracts by far the most solar energy and converts the most CO2 to sugars and proteins as compared to the more primitive forest ecosystems. (temperate forests produce almost no photosynthesis from fall all the way through winter and early spring while grasslands do produce photosynthesis with C3 cool season grasses and forbs) So the grasslands start out by fixing much more CO2 to begin with.

    Then we consider where the bulk of that fixed carbon is stored. In a forest it is mostly stored above ground in woody biomass and leaves. A large amount is also stored in the top O-horizon of the soil. Almost all this stored carbon will ultimately be returned to the atmosphere as CO2 and methane by fire and/or the processes of decay though. A climate scientist would call this short cycle carbon. A soil scientist calls it labile organic matter. It really isn't sequestered long term in any geological timeframe. (or at least most of it isn't)

    In a grassland we have much more primary productivity, but much less biomass storage as compared to forests. So the century's old question became what happened to all the rest? We sort of knew somehow it ended up as soil, because grasslands soils, particularly the Mollic epipedon, are many many times thicker and hold hundreds of times more carbon than most forest soils per acre on average. (there are some notable exceptions) But even that didn't quite add up. This is where the new research is beginning to reveal these questions.

    What we term the LCP is actually a biochemical pathway whereby CO2 first becomes fixed by photosynthesis, then becomes stored in the plants as sugar rich compounds and basic proteins forming sap, then flows downward through root exudates to feed symbiotic mycorrhizal fungi in trade for weathered and scavenged nutrients otherwise not bioavailable to the plant, metabolised into soil glues called "glomalin" to form a network of structured tunnels and pore spaces in the soil, which ultimately forms humic polymers tightly bound to the soil mineral substrate that creates new fertile soil.

    Climate scientists call this sequestered long cycle carbon to differentiate it from short cycle stored carbon in woody biomass. According to Dr Christine Jones in total approximately 40% of the total products of photosynthesis can follow this pathway under appropriate conditions and as it decays into soil about ~79% +/- of that carbon stays put rather than returning to the atmosphere as CO2. (again under appropriate conditions) Soil scientists call this stable carbon. However, the products of photosynthesis that are used by the grass to make above ground biomass also decay right back into CO2 much like the forests' above ground biomass. That's the labile carbon again. Well over 90% of labile carbon returns to the atmosphere as CO2 and methane on average. (with a few notable exceptions)

    So it is critical to understand that difference between what soil scientists call labile carbon and stable carbon or what climate scientists call short cycle and long cycle carbon. Grasslands take hundreds of times more short cycle carbon and divert it to long cycle carbon as compared to most forests. (with a few notable exceptions)

    You then asked, "Also, what is the proportional value of phytoplankton in this "sequestration" activity? And what is the impact of the recent news that some 40% of phytoplankton have disappeared from the world's oceans since 1952?"

    Frankly this does actually scare me. As a retired marine engineer I know that anyone who fails to respect the power of the ocean risks death. ANYONE and EVERYONE. As a metaphor, you seriously do not want to be around when Poseidon releases the Kraken. As you can probably tell, this causes my normally rational brain to short circuit into irrational fear. And I seriously do love the ocean! But it is ingrained in me that much through many trials and tribulations that we are absolute fools to mess with the ocean ecosystems as we are currently. It's the one thing actually powerful enough to cause human extinction.

    Back to rationality for a second though. I am not a marine researcher. Once years ago as a marine engineer on a research vessel I rubbed elbows with marine researchers occasionally, but I am not nor ever have been a marine scientist of any sort, not even amateur. Given that, I'll tell you what I have read over the years. One of the key things to remember is that most the ocean sequestration is focused around shallow seas and coastal areas with saltwater marshes and mangrove forests sequestering from 50-90% of biomass into stable forms. This is indeed one of those notable exceptions mentioned above. Also it is 2 to 35 times more carbon sequestration than even deep ocean phytoplankton! 

    Understanding Coastal Carbon Cycling by Linking Top-Down and Bottom-Up Approaches

    Some of that carbon came from the upland grasslands too though. Because those humic polymers that are tightly bound to the soil mineral substrate will generally stay bound when the soil erodes and floods coastal areas then settle out as silts. 

    You asked, "are you taking the position that animals grazing the Great Plains helped create the soil there ?"

    Yes. A resounding unequivocal yes! They co-evolved and the animals are every bit as important as the microbiome and the plants.

    Now for agriculture we can mimic this relationship if we understand how it functions. A cow is not a bison nor an antelope, but if we manage it correctly we can mimic that ecosystem function and use it to create soil too. But in order to do that you must first understand the function of the vast herds in a grassland/savanna/open woodland biome. 

    "Permaculture is a philosophy of working with, rather than against nature; of protracted & thoughtful observation rather than protracted & thoughtless labor; & of looking at plants & animals in all their functions, rather than treating any area as a single-product system." Bill Mollison

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  12. Red Barron

    You certainly are giving us a lot of info to chew on.  In Lexington, Virginia we have a Climate Change Seminar Series to consider nuanced aspects of the subject not considered by mass media.  I do not know your background or real name.  However, I am wondering if you would be willing to meet remotely via Skype, Zoom, or other platform to further this discussion with us.  We could likely get our science knowledgable people to help us evaluate your points.  I do appreciate your willingness to write so much with references to further our understanding.   From your messages, I know you want to spread your knowledge.

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    Moderator Response:

    [JH] I would advise against posting your telephone number on this site — or any other for that matter. If you would like us to delete it, please let us know. 

    PS - What is the name of the organization sponsoring the Climate Change Seminar series in Lexington, VA?

    [PS] Personal contact details removed as per request

  13. Our Climate Change Series is sponsored by the Environmental Committee of 50 Ways Rockbridge, a coalition of local political activist that formed after the 2016 federal elections.  Our purpose is to promote self education and activism. The Environmental Committee started out as the Climate Change Committee.  However, seeing existing environmental protections being dismantled, we felt the need to address those issues too, therefore Environmental Committee.  


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    Moderator Response:

    [PS] edited messages to moderator as per request. Rest of message is informative.

  14. RedBaron

    Don't think grazers have much to do with it. Bison never stomped through sixfoot prairie grass, head down, liable to run into a predator, they stayed along the rivers where there was water. The reason the white man killed off most of them was that the railroads ran close to the river floodplain and hundreds of riflemen could ride in open coaches and shoot the poor hapless creatures. There are thousands of square miles of the "Great American Desert" with hardly a creek, these areas were fostered by rainfall, not creeks. Those vast grasslands never saw a ruminant. Those grasses lived and died in soil delivered by the effects of the last ice age. Had the plow not dug the place up in a frantic attempt at dry land farming, it would still be a grassland and were it not for mining the Ogallala Aquifer, it would still be the Great American Desert...mostly empty of Bison more than a mile or two from the scarce rivers.

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  15. RedBaron

    But the rest of your observations are demonstratively "right on" and I am pleased to see it in print. Thank you.

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  16. I plan to chat with EliVA about it today

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  17. @swampfox, 

     You make an interesting hypothesis. However, your hypothesis lacks any evidence for it, and has quite a bit of evidence against it. So I would suspect you are a very very long way from supporting your assertions.

    More importantly as it applies to agriculture though, those who claim moving their cattle daily is indeed biomimicry are obtaining spectacularly better results than those who fence their cattle near streams and leave them there.

    There are huge improvements to both the animals and the grasses and forbs of the prairie and even a measurable increase in carbon sequestration of the soil when managed holitically with our new understanding of grassland ecology.

    We have fossilized paleosoil evidence:

    Cenozoic Expansion of Grasslands and Climatic Cooling

    We have observational evidence from YellowStone how predators forced herbivores away from lingering near rivers and how that improves ecosystem function.

    How Wolves Change Rivers

    In agriculture using biomimicry we have measurable evidence from modern tallgrass prairies:

    Grazing management impacts on vegetation, soil biota and soil chemical,
    physical and hydrological properties in tall grass prairie


    and from drier shortgrass prairie:

    Effect of grazing on soil-water content in semiarid rangelands of southeast Idaho


    Notice on the last two that there was even an improvement over the controls without any grazing.

    We even have evidence that many prairie grasses will simply die out if not periodically grazed or burned. This due to the grasses going moribund and choking on old material.

    Fire is a big component to the success of grasslands, large or small. Controlled burns, with a permit, are recommended every 4–8 years (after two growth seasons) to burn away dead plants; prevent certain other plants from encroaching (such as trees) and release nutrients into the ground to encourage new growth. A much more wildlife habitat friendly alternative to burning every 4–8 years is to burn 1/4 to 1/8 of a tract every year. This will leave wildlife a home every year and still accomplish the task of burning. The Native Americans may also have used the burns to control pests such as ticks. If controlled burns are not possible, rotational mowing is recommended as a substitute.

    One of the newer methods available is holistic management, which uses livestock as a substitute for the keystone species such as bison. This allows the rotational mowing to be done by animals which in turn mimics nature more closely. Holistic management also can use fire as a tool, but in a more limited way and in combination with the mowing done by animals.[1]

    So the weight of the evidence leads one away from the understanding you have and towards the new more modern understandings we recently discovered in just the last few decades.

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  18. RedBaron: Are you familiar with Oxford University's Food Clmate Research Network study "Grazed and Confused"? It asserts that regenerating degraded soils by converting them to pasture will indeed sequester carbon, but that soils cannot do this indefinitely. The study says that once a soil reaches capacity, the amount of carbon it can then sequester is minimal, and is outweighed by the methane emissions of the grazing cattle.

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  19. John @18,

    Yes I am familiar with this argument. It has three major flaws and many more minor flaws. 

    1.  While it may (or may not) be possible to locally saturate with carbon a pasture or even a region, there is no where near enough CO2 in the atmosphere to saturate the soil sink worldwide. And since for any AGW mitigation strategy to be effective we need world wide cooperation, this is really just a merchants of doubt type argument and can be safely dismissed as irrelevant.
    2. It also relies on the flawed assumption that the soil mollic epipedon when it does degrade and lose its carbon, that carbon would go back to the atmosphere as CO2 in a similar way as forests ecosystems. Rather instead that carbon when it does eventually leave the soil is much more likely to enter the geological long cycle for carbon. 
    3. That approach completely ignores the activity of methanotrophs on methane in grassland environments as if it did not even exist.


    No where better can we find an example of how poorly this is applied to regenerative agriculture/ permaculture than this statement right from the beginning:

    "This is to be achieved via intensification: for example by improving feed crop and animal breeding, optimising feed formulations, and by reducing the amount of land animals use, either by confining them in production units or by intensifying pastures.1

    The extensively reared ruminant – which predominantly feeds on grass – is the most problematic of creatures since its productivity is low in relation to the land and feed it requires, and the volume of gases it emits per unit of meat or milk output is great."

    That shows clearly they have not done their homework at all. They are comparing extensive agriculture with intensive (feedlot) agriculture, and actually doing a poor job of even that. But more importantly they are not even attempting to compare it to regenerative agriculture.

    Clearly intensive agriculture including CAFOs (feedlots) can in many cases produce more meat, milk and fiber than extensive agriculture, but the grazing techniques being considered for AGW mitigation are also intensive. Called MIRG (managed intensive rotational grazing), they actually produce more meat milk and fiber than conventional intensive ag. So right there it shows the entire work is irrelevant to the subject. They haven't even analyzed the right methods! They are not comparing intensive feedlot agriculture to intensive rotational grazing at all.

    I also think they made big systemic mistakes even in their analysis of extensive agriculture. Which for example is a net sink for both NO2 and CH4, yet because they have completely ignored the soil microbiome and its effect on atmospheric gasses, they have actually come to the rather ridiculous conclusion that somehow natural systems are causing anthropogenic global warming? Seriously? So now even breathing and passing gas is considered "emissions"? Clearly that group has a long way to go in understanding ecosystem function of plants, animals and microorganisms in a grassland biome. They are so far removed from reality it is kind of ridiculous and clownish. About the only part they got right is that intensive ag out produces extensive ag .... usually. Even that's not necessarily a given.

    Either way though for anyone making any claims of agriculture's impact on atmospheric greenhouse effect must at minimum include this:

    Soil Microorganisms as Controllers of Atmospheric Trace Gases
    (H2, CO, CH4, OCS, N2O, and NO)

    Keeping in mind of course, that was the state of the science 23 years ago. Their paradigm is so obsolete that it was obsolete decades ago and it is literally laughably behind now that knowlege of AMF ecosystem function has been added since 1996. Not to mention an orders of magnitude increase in knowlege of the soil food web.

    So yes, I know about flawed attempts to discredit attempts to change agriculture to sustainable methods, including flawed attempts to discredit the potential of the soil sink for carbon. However, this is a science based skeptic site and I highly recommend people here avoid going down that rabbit hole. 

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  20. RedBaron @19.


    Is 'this' relevant to your 'discussion'?

    “July 6, 2018 by Brandon Young
    Fixing Climate Change – Boosting Nature’s Cooling System
    . . . The best solutions for improving agricultural yields also happen to be the best way to solve climate change. They involve understanding the dynamics of the Earth’s soil-water-carbon system, and how it acts as a great sponge, and that this drives nature’s cooling and carbon draw down system at the local level, at the global level, and at all scales in between.”

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  21. @20 Postkey,

    Its not bad. I would have prefered more citations, but they got the systems science down pretty good.

    I just get annoyed when the systems science guys don't "show their work". (to steal a math metaphore) Makes it tough to find and verify the building blocks to the systems they describe. That leaves people like me hunting for them over weeks, months and even years sometimes.

    But ultimately yes, they appear to have the view of the forest rather than the trees based on my research of others who have come to the same overall conclusion. (independantly?)

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  22. Red Baron: On my farm I take soil samples and send them for testing. Results are reported for various nutrients and for organic matter(OM). My crop land OM runs around 4%. OM in my permanent pastures is constant at around 5.5%. Is the carbon that is sequestered through the anabolic processes you reference reflected in OM percentages in standard lab soil testing?

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  23. @John 22,

    To answer your question about SOC depends on the testing protocol used. Most importantly is a depth of at minimum 40cm. More commonly 100 cm gives a better more acurate figure. In a mature grassland the depths of soil sequestration can be 5 meters or more though. So a lot really does depend on depth of taking samples and the root depth of the species of grasses and forbs in your pasture. (as well as if they are C4 or C3 dominant blends)

    The conversion factor to obtain SOC from SOM is approximately 1.7 - 2 . So your grassland is approximately roughly 2.75% SOC and not even close to saturation even though apparently your gains may have stopped? As a general rule most grassland soils can fairly easily reach 6% SOC. After that they tend to get deeper rather than actually increasing SOC % much. (unless they are muck or peat based soils) 

    It would take a bit more investigation to say exactly why they stopped? If they did? But I suspect there is room for improvement if your goal is to use them as a carbon farming sink.

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  24. RedBaron

    Your post is a lot of stuff to look at. I'm not challenging your evidence except I think the Allen Savory "holistic" paradigm is a little wet on theory. Let us suppose that deploying massive numbers of herbivores, mainly bovines, to munch and defecate the Great Plains so as to "do" whatever it is that seems necessary to obtain the results. Where do we get the predators to drive them away from the waterways so that can disperse across the prairie, and yet at some point leave them alone so that they can re-hydrate, and since the Great Plains had those vast area where very little surface water exists, how many miles do they have to walk to get that water?  Hang with me for minute before we deal with that detail and I will ask one more question. How many cowboys with horses, hollers and lariats will be required to move these bovines, somewhat evenly across thousands of square miles of prairie so these bovine can provide this service to the grass...and once these critters have moved and "fixed" what needs fixing...what then? I think it would be fair to say that it would take millions of bovines to do this line of work and tens of thousands of cowboys to push them around. Seems implausible that millions of bovines, birthing, growing up, aging, dying or being slaughtered and fed to humans would reduce global GGEs, not to mention the problems of deploying cowboys who need to be fed, housed, and perennially made satisfied "riding the range" as a career choice...among other problems...some yet unforeseen.  And, of course, we'd have to kill all the bovine's predators since their presence would really foul up the works.

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  25. RedBaron

    Also the cite you provided regarding the research about the Cenozoic "conditions" was interesting and I have no particular challenge to it, but I'm curious as to whether the last ice age ending around 11,700 years ago might have mitigated the power of the evidence turn up in that paper. Surely, the grinding away of the surface by such a massive quantity of ice made major changes in soil characteristics and its general deposition, perhaps to the point that the post melt period of only 11,700 years was still quite significant in presenting to us what we see in the Great Plains today, less, of course, the effects of the 1930s dustbowl damage to the depth of the soil and what we see as the first several inches of the stuff that didn't blow away.

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  26. @swampfox,

    "Allen Savory "holistic" paradigm is a little wet on theory."

    Actually no. Just the opposite. There is some theory , but in general it is mostly "hands on" in the field real world experience and results made available to others in a way they can replicate without needing a PhD in theory.

    I have tried to explain HM to people and why your objections and questions simply don't apply. I even wrote a wiki page to document my research on it. However, many of the key elements keep getting removed by other editors including for a long time a concerted attack by dogmatic elements of society, so I keep needing to repeat it over and over. However, just so you can try to get it:

    There is a decision making framework that premptively solves all that before you do anything else, and constant monitoring to adapt to changing conditions so problems are actually solved before they even happen. Here is a copy of an important section removed from what I wrote on wikipedia about Holistic management:

    The holistic management decision-making framework uses six key steps to guide the management of resources:[1]

    1. Define in its entirety what you are managing. No area should be treated as a single-product system. By defining the whole, people are better able to manage. This includes identifying the available resources, including money, that the manager has at his disposal.
    2. Define what you want now and for the future. Set the objectives, goals and actions needed to produce the quality of life sought, and what the life-nurturing environment must be like to sustain that quality of life far into the future.
    3. Watch for the earliest indicators of ecosystem health. Identify the ecosystem services that have deep impacts for people in both urban and rural environments, and find a way to easily monitor them. One of the best examples of an early indicator of a poorly functioning environment is patches of bare ground. An indicator of a better functioning environment is newly sprouting diversity of plants and a return or increase of wildlife.
    4. Don't limit the management tools you use. The eight tools for managing natural resources are money/labor, human creativity, grazing, animal impact, fire, rest, living organisms and science/technology. To be successful you need to use all these tools to the best of your ability.
    5. Test your decisions with questions that are designed to help ensure all your decisions are socially, environmentally and financially sound for both the short and long term.
    6. Monitor proactively, before your managed system becomes more imbalanced. This way the manager can take adaptive corrective action quickly, before the ecosystem services are lost. Always assume your plan is less than perfect and use a feedback loop that includes monitoring for the earliest signs of failure, adjusting and re-planning as needed. In other words use a "canary in a coal mine" approach.

    That's just the framework of the plan every land manager makes before even starting. Each part of the framework will have details to follow that are case dependant.

    So to apply that decision making framework to your post at 24:

    Where do we get the predators to drive them away from the waterways so that can disperse across the prairie?

    Humans are the ones who do this using what fits the local cultural, social, economic and technological tools available and identified by the plan before even starting. So the Masai tribe in Kenya uses herders and monitoring like this:

    Rangelands rehabilitation and carbon credits in Kenya

    While in the Eastern US a completely different approach is taken:

    Polyface farms parts 1,2 and 3

    Australian outback another entirely different way:

    Tony Lovell - Savory Institute Putting Grasslands to Work Conference

    In fact every plan will be different for each and every farm. In fact I use it and I don't even raise any livestock at all currently! I simulate grazing with mowing and compost/mulches. That's actually the big deal about holistic management. It isn't a grazing system, its a way to develop a management system to accomplish those goals according to each and everyone's individual circumstances. So there is the managed intensive rotational grazing system, but it is used in the framework of holistic management.

    Polyface solves those issues you spoke about mostly with electric fencing and interns eager to learn for labor. The Masai in Kenya are already nomadic herders, so they change their lifestyle not much at all, for them its just training on soil sample protocol and learning a cooperative rotational system. In South America Horses and sheep or cattle are used a lot. There is a rancher in Texas that uses a helecopter and bison. There is no set way. Each management plan is adaptive and applies to local changing conditions and the tools available to the land manager.

    the Great Plains had those vast area where very little surface water exists

    It is true now, but very quickly after those regenerative practices are put into effect, the water returns. A big part of all this is the restoration of the natural hydrological cycle. See my citation @post 17. This is key for AGW mitigation as well, because it reduces the water evaporating and returns it to groundwater. Less water vapor means reduced greenhouse effect.

    I think you should see by now the rest of your questions are already answered. In some cases yes we could use cowboys. There still are professional cowboys here in Oklahoma and Texas. In other cases sheep or goat herders. In other cases electric fencing. In still other cases barbed wire and/or fencing. The tools and manpower for the job are identified right from the beginning when making the adaptive plan. Also the water sources and planned movements of the animals would be planned months or even a year in advance, with easily changed scheduling if needed due to unforeseen events in the future.

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  27. " A typical summer now has nearly half as much sea ice in the Arctic as it had in the 1970s and 1980s"


    The above is simply not correct.

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