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Messages - KiwiGriff

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1
Models are continually evaluated as to how they perform compared to observations and each other.

International climate scientists discuss first results from a new set of climate model simulations at the CMIP6 Model Analysis Workshop in Barcelona, Spain
9 April 2019

Quote
Under the auspices of the World Climate Research Programme (WCRP) Working Group on Coupled Modelling (WGCM), hundreds of climate researchers in modelling centres around the world are working to share, compare and analyse the latest results of global climate and Earth system models. Within the Coupled Model Intercomparison Project (CMIP), now in its 6th phase, project simulations of the research community provide model output that will fuel climate research and climate impact studies for the next 5 to 10 years, while its careful analysis will form the basis for future climate assessments. More than 40 climate modelling centres worldwide are expected to participate in CMIP6 and some early results are now available, which have been discussed at the first CMIP6 Model Analysis Workshop held in Barcelona, Spain, from 25-29 March 2019.

“I’m really excited to see the outcome of these first CMIP6 simulations. It is amazing how collaborative the scientific community is, and with the community-driven design of CMIP6, I expect we will make considerable progress on understanding how the Earth system responds to forcing, on identifying origins and consequences of systematic model biases, and on providing robust climate projections under different future scenarios that fill critical gaps compared to those used in CMIP5”, says CMIP Panel Chair Veronika Eyring from the German Aerospace Center (DLR). “This will include significant advances in our process understanding, supported by newly available evaluation tools that allow a more rapid and comprehensive evaluation of the models with observations”, says WGCM co-chair Cath Senior from the MetOffice Hadley Center in the UK.

At the time of the workshop, the CMIP6 archive included results from 12 modelling groups. As more modelling groups complete their simulations, the archive will become an increasingly rich resource for climate researchers. Based on new physical insights and newly available observations, many improvements have been made to models from CMIP5 to CMIP6, including changes in the representation of physics of the atmosphere, ocean, sea-ice, and land surface. In many cases, changes in the detailed representation of cloud and aerosol processes have been implemented. This new generation of climate models also features increases in spatial resolution, as well as inclusion of additional Earth system processes and new components. These additional processes are needed to represent key feedbacks that affect climate change, but are also likely to increase the spread of climate projections across the multi-model ensemble.
https://www.wcrp-climate.org/news/wcrp-news/1478-cmip6-first-results


   

2
Policy and solutions / Re: Greta Thunberg's Atlantic crossing
« on: August 16, 2019, 11:14:48 PM »
I would bet that the ratio of Aspies on this forum is greater than in the population at large.
We await the startling revelations as to what We are and how We think.

Greta has had more impact than any individual here, in all probability more than all of us here.
I wish her continuing success in shifting the overton window towards the changes humanity needs.

3
Policy and solutions / Re: Renewable Energy
« on: August 16, 2019, 10:43:30 PM »
Musk is a disruptor.
Many industry's are being shaken to the core by his company's.
He is driven and focused.
That makes him an arsehole to those he pushes past on his mission.
The fossil fuel industry and legacy auto manufactures  are being made obsolete by his actions.
When it comes to renewable energy he has probably made a bigger impact than any man alive
You don't have to like him to acknowledge his successes.  I follow Tesla because I am a gear head I follow green energy because I am concerned about humanity's future
I follow musk because he is making changes to the very  foundation of both these industry's.
Do I like or worship him ....nope ! I like  the impacts he is having on our world.

4
Thank you. I reconsidered that snark but you took it well  :)
We don't know. I have read that the blob is due to a slowing AMOC  .
But it is fascinating to learn  as we both are . Our shared ideas make us both more informed.
Quote
And a third point: in summer, the effect of heat flow through the sea surface should dominate, in winter the effect of ocean currents. That is because the well-mixed surface layer of the ocean is thin, so only the uppermost part of the ocean heat transport gets to affect the surface temperature. But the thin surface layer still feels the full brunt of atmospheric changes, and even stronger than in winter, because the thermal inertia of the thin summer surface layer is small. In our paper we analysed the seasonal cycle of the temperature changes in the subpolar Atlantic. The cooling in the “cold blob” is most pronounced in winter – both in the climate model (where we know it’s due to an AMOC slowdown) and in the observations. That yet again suggests the ‘cold blob’ is driven from the ocean and not the atmosphere.
http://www.realclimate.org/index.php/archives/2018/05/if-you-doubt-that-the-amoc-has-weakened-read-this/
Seems to suggest I may be part right as to why the blob is not apparent this summer.


5

Shows an anomaly value for ice off greenlands eastern coast.
Currents

Light blue surface current from there and north.
From a paper that has more information .
https://www.sciencealert.com/we-might-have-been-wrong-about-ocean-circulation-and-it-will-have-big-impacts

Just ideas neither of us know the answers .
Trashing world respected scientists work is easy on a blog not so easy to refute their ideas in published literature  .
The blob, AMOC and the effects of Greenlands increasing melt is a topic of research that is as yet unanswered.



6
Policy and solutions / Re: Renewable Energy
« on: August 15, 2019, 09:17:27 PM »
Long - term storage solutions ( week / month ) are needed
Why?
Building much more capacity than we need is far cheaper than building weeks of storage for edge cases.
The example in England was a cascade caused by one large fossil fuel plant failing . The same happened in Australia with the loss of one coal plant causing a cascade. Why does renewable energy get the blame for the effect of a fossil fuel plant failing ? A reasonable sized Battery system could have stabilized the grid for the few minutes needed to stop the cascade and shed load in a controlled manor. A Smarter grid with the ability to shed non essential loads like car charging will also go a long way to minimize such failures.

 

7
Consequences / Re: Laurentide II
« on: August 15, 2019, 09:00:21 AM »

North America Snow cover is declining in both spring and summer.
https://www.epa.gov/climate-indicators/climate-change-indicators-snow-cover

8
Policy and solutions / Re: Greta Thunberg's Atlantic crossing
« on: August 15, 2019, 08:31:30 AM »
Ocean sailors have a saying for unexperienced crew.
Sea sickness is mind over matter.
We don't mind you don't matter. :-\

Brave girl. An ocean voyage on a small boat is a huge adventure for anyone to undertake.
 May she not puke her guts out .


9
Science / Re: Trends in atmospheric CH4
« on: August 15, 2019, 08:23:39 AM »
This fits here somewhat.

Ideas and perspectives: is shale gas a major driver of recent increase in global atmospheric methane?
Abstract
Quote
Methane has been rising rapidly in the atmosphere over the past decade, contributing to global climate change. Unlike the late 20th century when the rise in atmospheric methane was accompanied by an enrichment in the heavier carbon stable isotope (13C) of methane, methane in recent years has become more depleted in 13C. This depletion has been widely interpreted as indicating a primarily biogenic source for the increased methane. Here we show that part of the change may instead be associated with emissions from shale-gas and shale-oil development. Previous studies have not explicitly considered shale gas, even though most of the increase in natural gas production globally over the past decade is from shale gas. The methane in shale gas is somewhat depleted in 13C relative to conventional natural gas. Correcting earlier analyses for this difference, we conclude that shale-gas production in North America over the past decade may have contributed more than half of all of the increased emissions from fossil fuels globally and approximately one-third of the total increased emissions from all sources globally over the past decade.
https://www.biogeosciences.net/16/3033/2019/
The fracked gas boom is not the breathing space on the way to carbon free some wish for.

10
Consequences / Re: Prepping for Collapse
« on: August 15, 2019, 03:33:20 AM »
We also are inclined to be horribly disrespectful of your social position.
Those who think they will come here and lord it over us will be in for a shock.
 
There was an interesting discussion here on talk back a few months back.
How will the elites who come here to bunker down keep their position if their money no longer buys loyalty? If your money is worthless along with your skills you will be prey.

11
Policy and solutions / Re: Direct Air Capture (of Carbon Dioxide)
« on: August 14, 2019, 01:01:30 AM »
Quote
Successful 1.9 W /m2 scenarios are characterized by a rapid shift away from traditional fossil-fuel use towards large-scale low-carbon energy supplies, reduced energy use, and carbon-dioxide removal.
Not presently possible with current technology on the scale we need. AKA magic thinking.

Models in CMIP6 are suggesting an ECS between 2.8C  and 5.8C. This compares with the previous coupled model intercomparison project (CMIP5), which reported values between 2.1C to 4.7C.
If so we don't need to follow the 8.5 emissions pathway to be facing truly catastrophic consequences.


12
Antarctica / Re: Majestic Antarctic Images
« on: August 10, 2019, 09:09:42 PM »
Melting of less compact ice in old crevasses when the mass was deeper in warm sea water?
Awesome photo by the way .

13
Greenland and Arctic Circle / Re: Where Does The Water Go?
« on: August 10, 2019, 01:24:51 AM »
Greenland Ice Melt Could Push Atlantic Circulation to Collapse.
https://www.hakaimagazine.com/news/greenland-ice-melt-could-push-atlantic-circulation-collapse/
Quote
In the North Atlantic, east of North America and south of Greenland, the ocean’s upper layers are much warmer than one might presume given the extreme latitude. This unexpected warmth is a product of the Atlantic Meridional Overturning Circulation (AMOC), a vitally important system of ocean currents that moves warm salty water northward from the tropics and cold fresher water south. The AMOC looms large in the Earth’s climate: it is responsible for redistributing nutrients throughout the Atlantic Ocean and is a major driving force controlling the climate on both sides of the pond.

Ocean currents all experience fluctuations, which can dramatically change the distribution of nutrients, heat, and fish. The best known example is probably the El Niño-Southern Oscillation, in which unusually warm water occasionally disrupts the Pacific Ocean’s Humboldt Current that flows north from Chile toward Peru. El Niño events can shift the jet stream south, cause excessive rainfall and devastating floods, and temporarily collapse fish stocks.

To date, most climate research suggests that the AMOC is relatively stable and carries water throughout the ocean in a reliable, repeating cycle. But anthropogenic climate change seems to have made the current weaken slightly, raising the question of whether more dramatic shifts are in store. As of the most recent Intergovernmental Panel on Climate Change report, a shutdown of the circulation from further warming is considered unlikely. Yet a new study says that the unprecedented melting of Greenland’s massive ice sheets, previously overlooked in most climate modeling, will result in the AMOC weakening, and maybe even collapsing, within the next 300 years.
based on the paper.
Fate of the Atlantic Meridional Overturning Circulation: Strong decline under continued warming and Greenland melting
P. Bakker etal.2016
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL070457
Abstract
Quote
The most recent Intergovernmental Panel on Climate Change assessment report concludes that the Atlantic Meridional Overturning Circulation (AMOC) could weaken substantially but is very unlikely to collapse in the 21st century. However, the assessment largely neglected Greenland Ice Sheet (GrIS) mass loss, lacked a comprehensive uncertainty analysis, and was limited to the 21st century. Here in a community effort, improved estimates of GrIS mass loss are included in multicentennial projections using eight state‐of‐the‐science climate models, and an AMOC emulator is used to provide a probabilistic uncertainty assessment. We find that GrIS melting affects AMOC projections, even though it is of secondary importance. By years 2090–2100, the AMOC weakens by 18% [−3%, −34%; 90% probability] in an intermediate greenhouse‐gas mitigation scenario and by 37% [−15%, −65%] under continued high emissions. Afterward, it stabilizes in the former but continues to decline in the latter to −74% [+4%, −100%] by 2290–2300, with a 44% likelihood of an AMOC collapse. This result suggests that an AMOC collapse can be avoided by CO2 mitigation.

.Discussion by S Rahmstorf at real climate on a paper of his on same subject.
.http://www.realclimate.org/index.php/archives/2015/03/whats-going-on-in-the-north-atlantic/
What’s going on in the North Atlantic?

Quote
The North Atlantic between Newfoundland and Ireland is practically the only region of the world that has defied global warming and even cooled. Last winter there even was the coldest on record – while globally it was the hottest on record. Our recent study (Rahmstorf et al. 2015) attributes this to a weakening of the Gulf Stream System, which is apparently unique in the last thousand years.

The whole world is warming. The whole world? No! A region in the subpolar Atlantic has cooled over the past century – unique in the world for an area with reasonable data coverage (Fig. 1). So what’s so special about this region between Newfoundland and Ireland?
Fig. 1 Linear temperature trend from 1900 to 2013. The cooling in the subpolar North Atlantic is remarkable and well documented by numerous measurements – unlike the cold spot in central Africa, which on closer inspection apparently is an artifact of incomplete and inhomogeneous weather station data.

It happens to be just that area for which climate models predict a cooling when the Gulf Stream System weakens (experts speak of the Atlantic meridional overturning circulation or AMOC, as part of the global thermohaline circulation). That this might happen as a result of global warming is discussed in the scientific community since the 1980s – since Wally Broecker’s classical Nature article “Unpleasant surprises in the greenhouse?” Meanwhile evidence is mounting that the long-feared circulation decline is already well underway.

Impacts.
Global and European climate impacts of a slowdown of the AMOC in a high resolution GCM
C. Jackson et al.
Abstract

Quote
The impacts of a hypothetical slowdown in the Atlantic Meridional Overturning Circulation (AMOC) are assessed in a state-of-the-art global climate model (HadGEM3), with particular emphasis on Europe. This is the highest resolution coupled global climate model to be used to study the impacts of an AMOC slowdown so far. Many results found are consistent with previous studies and can be considered robust impacts from a large reduction or collapse of the AMOC. These include: widespread cooling throughout the North Atlantic and northern hemisphere in general; less precipitation in the northern hemisphere midlatitudes; large changes in precipitation in the tropics and a strengthening of the North Atlantic storm track. The focus on Europe, aided by the increase in resolution, has revealed previously undiscussed impacts, particularly those associated with changing atmospheric circulation patterns. Summer precipitation decreases (increases) in northern (southern) Europe and is associated with a negative summer North Atlantic Oscillation signal. Winter precipitation is also affected by the changing atmospheric circulation, with localised increases in precipitation associated with more winter storms and a strengthened winter storm track. Stronger westerly winds in winter increase the warming maritime effect while weaker westerlies in summer decrease the cooling maritime effect. In the absence of these circulation changes the cooling over Europe’s landmass would be even larger in both seasons. The general cooling and atmospheric circulation changes result in weaker peak river flows and vegetation productivity, which may raise issues of water availability and crop production.
https://link.springer.com/article/10.1007/s00382-015-2540-2




14
Policy and solutions / Re: Direct Air Capture (of Carbon Dioxide)
« on: August 09, 2019, 10:59:39 PM »
Quote
what Brazil will be doing to the Amazon.

What we are doing to the Amazon.
If we hit 3C there is a good chance that the amazon region will transition from rain forest to  savannah.
This change will release much of the carbon contained in the present forest.
Not being all skyrockety the change  will  happen over century's not decades.
Earth system sensitivity is  higher than the usually quoted ECS equilibrium climate sensitivity.
Deforestation of the Amazon being one of the feed backs not addressed in ECS calculations.


15
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: August 06, 2019, 02:00:13 AM »
 ;D
My comment above got many attempts to shoot it down in flames.
I was guilty of grossly over simplifying due mostly to a comment made on a cell phone and my laziness. My expectation was that the audience would know enough to read what I was implying not what I said.
Science folks, the art of being less wrong.
I maintain I was less wrong than some of the replies.

We have claims that a feed back,more  heat escaping from the open water  over winter due to low extent, has resulted in a change in the long term trend of decline.
This seems to me to be based on cognitive bias, a selective use of the available data and a curve fitting exercise.
Noise.
Using the effects of a few weather events to add an extra term into the curve of decline is questionable. Such ideas strongly reminds me of the so called "pause" in warming that certain sectors pushed after 1998's excursion from the long term trend in global mean surface temperatures.
Ocean heat content below the ice has continued its rise. Atmospheric temperatures above the ice have continued to increase. Volume,thickness and area has continued to fall.
None of these metrics support a change to the shape of the long term trend.

At some point in the next decade or two we will see another weather event that results in a BOE.
Extent  will then revert back to the trend in the following years. After a single BOE has happened once it will happen again with increasing frequency.
Such events will  hasten a blue ocean over summer becoming a permanent state. 

FWIW.
DK?
I know just enough to know I don't know enough to know how much I don't know.



16
Policy and solutions / Re: Extinction Rebellion
« on: August 05, 2019, 09:45:49 AM »
Sailing on a boat that was going there anyway has a very low carbon impact compared to adding your weight to a big metal  bird burning aviation fuel.
Without doubt the impact of Greta travelling to the USA will result in a far greater saving of carbon emissions than her journey will require.

The attacks on her disgust me  especially the ones on her Asperger's.
They are no longer getting traction in attacking the science so they are turning up the attacks on the messengers and the message.

17
Walking the walk / Re: Master List of Easy Changes?
« on: August 05, 2019, 03:35:55 AM »
Not quite the same as a septic tank.
 We have a considerable issue in this country with older septic tanks  contaminating the environment with human waste.
A septic system is  just a large tank that allows solids to settle out and the remaining liquid to permeate the surrounding ground. Once full the remaining toxic  sludge must be pumped out and dumped into a land full. Septic tank systems  no longer comply with building standards here in NZ. Most of the alternative   systems use pumps and aerators to help digest the solids. Such mechanical pumps would represent a constant drain on a limited energy supply and also are proving costly to maintain with the pumps needing to be replaced frequently.
What we have installed is a vermiculture based bio digester that hopefully will run at no cost and little maintenance for my remaining life span.

Before we moved our houses onto here we actually had a small portable worm based composting toilet  that worked very well as a temporary solution.

Hopefully  this  information is close enough to the threads topic to not cause offence.....

18
Walking the walk / Re: Master List of Easy Changes?
« on: August 04, 2019, 09:54:27 PM »
When it's yellow, let it tallow. When it's brown, flush it down
 ;D
Some of us do not have to abide by such imperatives .
I generate 100% of my  electricity from solar and source all domestic water from the roof .
Human waste is  gravity fed  into a colony of Eisinia fetida and from there into regenerating  native forest.
The more I flush the bigger the trees grow ......

19
Consequences / Re: Places becoming less livable
« on: August 04, 2019, 07:29:35 AM »
New Zealand West coast beaches battered by huge storm waves and king tides.
Quote
There’s warning of an imminent ecological disaster on the South Island’s West Coast as heavy seas threaten to expose an old rubbish tip.

Officials fear it’ll be a repeat of the Fox River landfill spill earlier this year.

About seven to 10 metres of coastline has been eaten away by big swells and kingtides after the coast was battered by storm surges today.

But while coastal residents spend another night out of their homes, there’s growing concern that the next high tide will unleash a much bigger problem for the area.

A number of households in Westport were send packing overnight as a combination of heavy swells and high tide landed straight on their doorstep.

Hector resident Sarah Godsiff told 1 NEWS a big wave swept into her home.

The hammering of the waves was felt from Punakaiki up to Karamea.

“Last 24 hours we’ve lost along this coastline anything from seven to 10 metres where there’s a weakness in the embankments,” Buller mayor Gary Howard says.

The sea spat debris everywhere, testing a new fence built to protect the airport runway.

However, it will take a further battering with three days of bad weather still to come.
https://www.tvnz.co.nz/one-news/new-zealand/landfill-close-being-swept-away-huge-waves-pummel-west-coast
As always you can not lay the blame for a single weather event on AGW .
Sea level rise is accelerating  and wave heights in the southern ocean are also rising due to the effects of climate change.
Quote
Extreme ocean winds and wave heights are increasing around the globe, with the largest rise occurring in the Southern Ocean, University of Melbourne research shows.
 
https://www.sciencedaily.com/releases/2019/04/190425143540.htm
Such headlines are only going to become more familiar.

20
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: August 01, 2019, 10:51:20 AM »
Visible light warms the ocean as far as it can penertrate. In blue water this can be to 50 meters or more.
The ocean radiates energy in the infrared from a surface skin of only a few microns depth.
As long as it is still cold enought to ice over the surface film in winter once the sun is gone and insulate the water belowe the winter radiation  is moot .
The deeper ocean will still hold most the energy it has absorbed over an ice free summer .
 The amount of energy radiated from the ocean to space will not change signifactly until the ice is gone year around .
We will be lucky to still be able to observe the arctic if it does get that warm.


21
Policy and solutions / Re: Tesla glory/failure
« on: July 09, 2019, 09:52:22 PM »
Quote
The competition is showing up. This is why the S and X sales have been crushed. There are now good alternatives now. Presently, the model 3 alternatives are arriving.


The X and S have competition from  the 3.
No one has produced a car that can compete with any of Tesla offerings.
Feel free to point out one other manufactures product that can beat even one of these metrics let alone all of them.
Range.
Efficiency.
Acceleration.
Charging rate.
Charging infrastructure.

Outside of the USA the S and X are to large for most markets.
The large sedan market is contracting In the USA.
The S is a niche product that had been selling well outside of it true market position because there was no alternative. The 3 has changed that market not the products from Jag, Hyundai and VW group.

Consider.

Sourced from inside ev's.





22
Policy and solutions / Re: Tesla glory/failure
« on: July 08, 2019, 12:31:52 PM »
Quote
USED Modules from 85 kwatt Tesla Model S battery packs.  The modules consist of 444 Panasonic 18650NCR cells  3400 mAh nominal capacity. Dismantled from Tesla model S with less then 60.000 km

    dimensions: 685 x 300 (280) x 75 mm (l x w x h).
    Weight: 25 kg
    Voltage range: 24,9 vdc to 18,6 VDC
    Capacity: 5,3 kwhr
    Wiring and original BMS PCB board still included.

https://eveurope.eu/en/product/tesla-model-s-module-53-kwhr-24/

I understand that Tesla replaces the entire battery under warranty but only guarantees to supply a  unit with pro rata performance so is probably replacing the modules as needed to make up the replacement battery's.

I do not think the modules them self's are able to have individual cells replaced.

The model three has a different architecture but still modular in design.
Model 3 modules seen in this vid .
https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-mysterious-and-alluring-work-in-progress.

Hopefully when my present storage system expires in five or so years Tesla or similar battery systems  packaged with suitable inverters will be an affordable alternative to replace lead acid off grid .
 





 

23
Science / Re: Magnitude of future warming
« on: July 04, 2019, 03:44:00 AM »
Quote
The nations that have signed agreements to stabilize the global mean temperature by 2050 will fail to meet their goals unless existing fossil fuel-burning infrastructure around the world is retired early, according to a study—published today in Nature - by researchers at the University of California, Irvine and other institutions.

... According to the study, emissions from existing energy infrastructure take up the entire carbon budget to limit mean warming to 1.5 degrees Celsius and close to two-thirds of the budget to keep warming to under 2 C over the next three decades.

Still does my head in that we see claims we can stay below 1.5C .
We shutter  Coal plants  we get most of the 0.4C that our aerosols emissions are shading us from  immediately. Add that there is some delay between CO2 emissions and warming giving another 0.2C or more the math for 1.5 C simply does not work.

In the longer term
Long distance transport , steel and cement manufacturing do not have viable economic solutions to their emissions as yet.  CCS is another technology solution  we do not have a viable answer to.
Taking these factors into account there is no real pathway towards net zero and reducing the 415ppm CO2 we have already achieved hence the 1.5C warming we have locked in .

The 1.5C target is just a mythical dream based on magic thinking  not an achievable goal

0.4C value for aerosols from Haustein et al, 2019 most of which is from burning FF's to make electricity .




24
The forum / Re: Forum Decorum
« on: July 02, 2019, 01:16:37 AM »
A Team is to valuable to lose to the forum.
Maybe a dedicated thread restricted to a few chosen ones  for his input is warranted. With a parallel thread for the rest of us to gibber about A Teams output without anyone having to wade though our noise to access his pearls of wisdom.

25
IPCC SR15's carbon budget to stay below a 1.5C :P

Aerosols mostly from burning hydrocarbons result in approximately  0.4C of cooling.
This cooling influence is going to reduce at the same rate as we reduce emissions .
Presently we are above preindustrial by about 1.25C and warming at 0.2C a decade. 

The fact that a budget for staying below 1.5C  is talked about by the IPCC or anyone else supposedly informed by the science does my head in.
The "Budget for 1.5C" was gone at  lest a decade ago.

26
Which of course goes alongside this.

https://science.sciencemag.org/content/364/6440/548
Ocean winds blowing harder
Quote
Two frequently asked questions about how climate warming will affect the environment are whether windiness might change and what effects that might have on ocean waves. Young and Ribal analyzed global satellite data over the period from 1985 to 2018 to determine if there are any trends in oceanic wind speed and wave height. They found small increases in both quantities, with the strongest increases in extreme conditions and in the Southern Ocean. These findings are important for understanding air-sea exchange of energy and carbon dioxide and for projecting sea levels during storms.

Science, this issue p. 548
Abstract

In this study, global satellite data were analyzed to determine trends in oceanic wind speed and significant wave height over the 33-year period from 1985 to 2018. The analysis uses an extensive database obtained from 31 satellite missions comprising three types of instruments—altimeters, radiometers, and scatterometers. The analysis shows small increases in mean wind speed and significant wave height over this period, with larger increases in extreme conditions (90th percentiles). The largest increases occur in the Southern Ocean. Confidence in the results is strengthened because the wind speed trends are confirmed by all three satellite systems. An extensive set of sensitivity analyses confirms that both the mean and 90th percentile trends are robust, with only small impacts caused by satellite calibration and sampling patterns.

The higher sea states are  already impacting on west coast erosion rates here in NZ along with the anomalous regional rise in sea level.

27
With sea level rise it will be higher storm surge that has significant impacts first.
We have already seen New York badly impacted with tropical cyclone  sandy.
It will not be the slow  rise of sea level that causes eventual retreat it will be weather events causing catastrophic damage and sane evaluation of the costs and futility of repeated repair. The developed world is far more susceptible to such costly events than the poor regions of Bangladesh.

Seeing as I have commented on this thread.
Thanks ASLR I have been reading your output for years and appreciate the immense amount of effort  your do in constructing your well supported narrative.

28
Consequences / Re: Hurricane Season 2019
« on: June 11, 2019, 07:56:41 AM »



Percentage increase 1980 to 2016 (as a linear trend) in the number of tropical storms worldwide depending on their strength. Only 95% significant trends are shown. The strongest storms are also increasing the most. Red colors show the hurricane category on the Saffir-Simpson scale. Graph by Kerry Emanuel, MIT. Creative Commons License CC BY-SA 3.0.

Quote
A significant global increase (95% significance level) can be found in all storms with maximum wind speeds from 175 km/h. Storms of 200 km/h and more have doubled in number, and those of 250 km/h and more have tripled. Although some of the trend may be owing to improved observation techniques, this provides some evidence that a global increase in the most intense tropical storms due to global warming is not just predicted by models but already happening.

However, global warming does not only increase the wind speed or frequency of strong storms (which is actually two ways of looking at the same phenomenon, as frequency depends on wind speed).  The average location where the storms are reaching their peak intensity is also slowly migrating poleward (Kossin et al. 2014) and the area where storms occur expands (Benestad 2009, Lucas et al. 2014), which changes patterns of storm risk and increases risk in regions that are historically less threatened by these storms (Kossin et al. 2016).

Most damage caused by tropical storms is not directly caused by the wind, but by water: rain from above, storm surge from the sea. Harvey brought the largest amounts of rain in US history – the probability of such a rain event has increased several times over  recent decades due to global warming (Emanuel 2017; Risser and Wehner, 2017; van Oldenborgh et al., 2017). Not least due to global warming, sea levels are rising at an accelerating rate and storm surges are becoming more dangerous. A recent study (Garner et al. 2017), for example, shows that the return period of a certain storm surge height in New York City will be reduced from 25 years today to 5 years within the next three decades. Therefore, storm surge barriers are the subject of intensive discussion in New York (Rahmstorf 2017).

While there may not yet be a “smoking gun” – a single piece of evidence that removes all doubt – the weight of the evidence suggests that the thirty-year-old prediction of more intense and wetter tropical cyclones is coming to pass. This is a risk that we can no longer afford to ignore.

http://www.realclimate.org/index.php/archives/2018/05/does-global-warming-make-tropical-cyclones-stronger/

My view of KK is as an optimist rather than a straight out denier.
I view my self as a realist though you can call me a pessimist '
Climate change  is a matter if risk. It far better to eer on the side of caution  when so much is at stake.

29
Science / Re: Magnitude of future warming
« on: June 01, 2019, 06:04:19 AM »
Global financial crisis 2007 to 2008. Emissions shrank along with the global economy for a number of years.
So the start point was effected by circumstance .
We then use an average for the entire period rather than the much more important trend
After all the the measurement of CO2 is  referred to as the keeling curve for a very simple reason. Acceleration.

As this forum is mostly populated by the informed an interesting distraction .
But for our purpose .
The important number for humanity is  CO2e not CO2.

 

30
Walking the walk / Re: Passive / green House Design
« on: May 31, 2019, 05:08:13 AM »
We just completed a passive designed beach house here in the far north of NZ
I know we dont dont get the extremes of temperature continental climes  at 35 degrees do due to the effects of the oceans that surround NZ.
Our daily temperature varies between 15 to 30C in summer and 5 to 20C in winter.
Building for passive solar with large windows shaded by eaves on the northern (sunny) side and only very small windows on the south means we have yet to use the heat pumps we installed as part of the build.
Having though flow allows us to easily modulate temperatures . When we arrive for a weekend in summer the house is often over 40C internally from being closed up .
In ten minutes we can pull that down to ambient just by opening windows on both cool dark and warm light side getting a flow of air even when it is still.  The eaves mean we do not get direct light in the height of the day in summer. In winter the large windows easily heat the house to a comfortable temperature.
Unfortunately due to the site topography we had to use wooden floors not a concrete slab so we do not have a large  heat sink to modulate temperatures efficiently instead have to rely more on insulation. 
Efficient thermal design seems to be lacking from much of the building industry thinking. Much effeminacy gain can be achieved with just a little thought if you are aware of the possibility .

Due to the huge price drops over the last few years Using  a few PV panels and an immersion heater would be both cheaper and more reliable long term than solar heating panels as it is easier to route and maintain wiring than a thermal liquid based system.

It seems that the potential of many such technology's  are not common knoldge as yet among the building fraternity. I even had to educate my electrician on how solar works and what it can actually do when I called him to to certify my home power system. The best approach is research for the subject your self to not rely on experts as they do not often as yet get the training needed to understand what you are thinking  about.
 

31
Consequences / Re: World of 2030
« on: May 09, 2019, 10:02:39 AM »
Hi all long time lurker who thought he could finally add some value.

Tamino has done a few posts on sea level.
in this one he gives the present rate as about 4.8mm a year.
 https://tamino.wordpress.com/2018/02/13/sea-level-acceleration-2/
His  post also discuses a paper were the researchers estimated, and removed, the influence of ENSO/PDO as well as the major volcanic eruption of Mt. Pinatubo.
Climate-change–driven accelerated sea-level rise detected in the altimeter era
R. S. Nerem Et al.
https://www.pnas.org/content/115/9/2022
Their result was 4.3 mm/y accelerating at 0.084 mm/y2.

2030?
0.3C warmer 0.2C from CO2 induced AGW  0.1C due to a reduction of aerosols in china .
BOE  in the arctic has happened at lest once .
Grounding line retreat in one of the major antarctic glaciers has made the world really start to take notice  of accelerating sea level rise.
The USA has been hit by a historic cat five storm.
We  only just start to see the keeling curve stop accelerating.
The Gt barrier reef is for all intents dead and the resulting collapse of  marine ecology's is showing though out the Western Pacific.
Periodic Food shortages due to weather extremes have caused the collapse of at lest one nation in both Africa and the middle east.
More country's fall to the far right in a reaction to social economic pressures.
We are still arguing about if AGW is real with a faction of deniers on line.
The loud political talk about addressing emissions  is still not resulting in sufficient action towards net Zero CO2.


 

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