[HN Gopher] Wetland emission and atmospheric sink changes explai...
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       Wetland emission and atmospheric sink changes explain methane
       growth in 2020
        
       Author : pseudolus
       Score  : 49 points
       Date   : 2022-12-15 13:42 UTC (9 hours ago)
        
 (HTM) web link (www.nature.com)
 (TXT) w3m dump (www.nature.com)
        
       | torcete wrote:
       | I literally just finished watching this video with a presentation
       | by astrophysicist Valentina Zharkova titled:
       | 
       | "In next 30 yrs, global warming prob. will be last thing in our
       | mind"
       | 
       | https://www.youtube.com/watch?v=LYOMKLDbeYE
       | 
       | And to be honest, I don't know what to think anymore.
        
         | mturmon wrote:
         | About VZ: No time to watch that video, but she has been
         | proposing solar explanations for the observed temperature
         | changes, so I assume that's the topic.
         | 
         | There are a lot of reasons to reject changes in solar forcing
         | as an explanation for _recent_ warming (as opposed to
         | Milankovitch cycles) - and it has been rejected, although 15
         | years ago it was still treated seriously. Also, the CO2 rise is
         | very real, and the link of CO2 to warming is clear.
         | 
         | It's easy to watch/read "point explanations" for climate
         | phenomena, and get confused. ("I read this paper from 2015 in
         | _Nature_ and ... ".) One reason is that laypeople, even those
         | with physics backgrounds, just don't have enough background
         | information to put claims in context. Earth science is hard -
         | so many interacting systems.
         | 
         | A better source for motivated laypeople is the NCA - the
         | National Climate Assessment - see
         | https://nca2018.globalchange.gov . It's done every 5 years, and
         | the next one is due in 2023.
        
         | mistrial9 wrote:
         | this has the outward appearance of an aging attention-seeker
         | with excellent credentials from forty years ago?
        
         | hannob wrote:
         | If you don't know what to think when some person on youtube
         | says one thing and a large collaboration of scientists who are
         | the world's experts of a field (the IPCC) says the opposite in
         | detailled reviews of the current science then you should
         | probably start by learning a few basic things about the
         | scientific process.
        
       | defrost wrote:
       | This is one of the cascade effects predicted some time ago
       | 
       | > We found that most wetland areas of the world were exposed to
       | warmer and wetter conditions in 2020 than normal years ...
       | 
       | ... leading to greater methane growth.
       | 
       | A central reason for concern by geoscientists about human C02 and
       | the boiling frog scenario is that slow rises in C02 eventually
       | lead to warmer wetter conditions and then a subsequent positive
       | feedback increase in water vapor and methene .. which are even
       | better heat blankets than C02.
        
         | ecommerceguy wrote:
         | Time to sell my beach front property.
        
           | vkou wrote:
           | The problem with climate change isn't sea level rise, or the
           | occasional heat wave that kills a few hundred or thousand
           | people in your area, the problem is food security and
           | political instability and creating refugees.
        
             | autoexec wrote:
             | Sea level rise is already a problem and it's costing a lot
             | of money to continuously repair flooding damage and to keep
             | things from getting worse. There's also the problems of
             | increasingly severe storm damage along the coasts. People
             | will absolutely be driven inland by climate change. and if
             | we were smart we'd start pulling back now, and avoid
             | throwing away huge amounts of money year after year after
             | year just so people can pretend it's not happening.
        
           | danuker wrote:
           | You could buy cheap property in currently cold regions. But
           | only expect the ROI to occur after enough warming (decades).
        
         | landemva wrote:
         | This describes the cycles which have taken place in the past.
         | There apparently was enormous amounts of foliage (CO2
         | consumers) during time of dinosaurs. I expect these planet-
         | scale cycles to continue.
        
           | sidewndr46 wrote:
           | If you're talking about the Carboniferous period, my
           | understanding is that was a one time thing. There were no
           | organisms to break down wood and other plant matter during
           | that time period. Huge amounts of lignin in the trees meant
           | that it just got buried as sequestered carbon. That won't
           | happen a second time since nowadays it is possible for all
           | modern trees to be decomposed by a subset of living
           | organisms.
        
       | photochemsyn wrote:
       | > "In addition, the year 2020 was exceptionally hot from early
       | spring to late summer over northern Eurasia, a sensitive region
       | for CH4 emissions from biogenic sources such as wetlands,
       | permafrost slumps and arctic lakes, which are expected to emit
       | more CH4 as the temperature increases."
       | 
       | I wish people would be realistic and just admit that the tipping
       | point for climate is in the past - because even if there was
       | complete elimination of fossil fuel use in the next decade
       | (highly unlikely), polar warming has resulted in permafrost melt,
       | so that's going to keep dumping carbon to the atmosphere at a
       | slow steady rate. At best, elimination of fossil fuels over the
       | next 3-5 decades will only result in slower warming over the last
       | few decades of the 21st century. We also haven't even come close
       | to realizing warming from the past 5 decades, as the time-to-
       | equilibrium for current forcing is ~100 years. This means a
       | return to climate conditions last seen 3-5 million years ago,
       | during the Pliocene.
       | 
       | Practically, this means as much will have to be spent on
       | adaptation to new conditions as will have to be spent on
       | transition to a non-fossil energy system.
        
         | [deleted]
        
         | mistrial9 wrote:
         | each of the IPCC, World Meteorological Association, US Global
         | Change Study and the California Climate Reports, contain
         | specifics on this .. a list most recent publications with
         | citations next up?
        
           | mistrial9 wrote:
           | ... about halfway through searching a pile of reports.. so
           | far all of these mention a permafrost/wetlands amplification
           | cycle
           | 
           | Special Supplement to the Bulletin of the American
           | Meteorological Society Vol. 100, No. 9, September 2019 (see
           | also 2015)
           | 
           | Blunden, J. and D. S. Arndt, Eds., 2019: State of the Climate
           | in 2018. Bull. Amer. Meteor. Soc., 100 (9), Si-S305,
           | doi:10.1175/2019BAMSStateoftheClimate.1
           | 
           | Chapter 19 Climate Change -- Evidence & Causes An overview
           | from the Royal Society & the US National Academy of Sciences,
           | 2014 (paid for partly with Sackler Money !! cannot make this
           | up)
           | 
           | THE UNDERSTATEMENT OF EXISTENTIAL CLIMATE RISK BY DAVID
           | SPRATT & IAN DUNLOP 2017. Revised and updated August 2018.
           | 
           | D E P A R T M E N T O F D E F E N S E C L I M AT E C H A N G
           | E ADAPTATION ROADMAP 2014
           | 
           | Climate Change and the Electricity Sector: Guide for Climate
           | Change Resilience Planning September 2016 U.S. Department of
           | Energy Office of Energy Policy and Systems Analysis
           | 
           | --
        
           | culi wrote:
           | Not sure what your point is.
           | 
           | The very first IPCC report (1.5degC) completely ignored
           | permafrost.[^0] They basically admitted they didn't have data
           | on it so they will just ignore the effect altogether. The
           | IPCC reports that followed have all been increasingly grim.
           | In large part, imo, because they stopped ignoring permafrost
           | 
           | [^0]: IPCC chapter 2:
           | 
           | > The reduced complexity climate models employed in this
           | assessment do not take into account permafrost or non-CO2
           | Earth system feedbacks, although the MAGICC model has a
           | permafrost module that can be enabled. Taking the current
           | climate and Earth system feedbacks understanding together,
           | there is a possibility that these models would underestimate
           | the longer-term future temperature response to stringent
           | emission pathways (Section 2.2.2).
        
         | scythe wrote:
         | Well, there's still iron-salt aerosol geoengineering for
         | atmospheric methane removal. Big bet, though.
        
           | winReInstall wrote:
           | Rather prefer space based foil-solar sail ice cap shielding
           | and artifically growing glaciers near south and northpole..
        
             | hedora wrote:
             | Or, direct air carbon capture. Getting to net zero would
             | cost ~ $1 / gallon of gasoline (and equivalent for other
             | things that emit.) I think we should be paying ~ twice
             | that, minimum.
             | 
             | It's far less risky than trying to block out the sun.
        
         | tony_cannistra wrote:
         | I'm not aware of any evidence of this, actually. Can you point
         | to some?
        
           | photochemsyn wrote:
           | Search Google Scholar for "committed warming" for a quick
           | intro. For example:
           | 
           | > "We have asked the illustrative but specific question of
           | should atmospheric greenhouse gases suddenly stop increasing,
           | what additional global warming will occur based on current
           | understanding? Such a constant composition commitment is less
           | ambitious than the recent aspiration of many to achieve "net-
           | zero" global emissions of GHGs. Net-zero has been generally
           | defined as not including natural sinks and is only achieved
           | when anthropogenic CO2 emissions are balanced globally by
           | anthropogenic removals. "
           | 
           | (2020) "CMIP6 climate models imply high committed warming"
           | 
           | Read the paper at sci-hub, check the references for more.
           | 
           | https://sci-hub.se/10.1007/s10584-020-02849-5
           | 
           | As this paper notes,
           | 
           | > "...there is often a misunderstanding in society,
           | corresponding to a belief that achieving constant atmospheric
           | GHG composition implies that global mean temperatures will
           | not change from that point forward."
           | 
           | Note also that these models are generally not including the
           | non-anthropogenic feedback process, such as permafrost melt
           | and carbon release, and the relatively uncertain but
           | potentially very large effects of methane release from
           | shallow marine sediments due to warming polar oceans.
        
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