PART 10/ Opdaterede Sol/Is/temp/hav data

Peter Villadsen skrev:
Ulrike Pielmeier fortæller i Facebook gruppen "Klimarealisterne":

Godt spottet fra Lars Brandt. Man hører ofte hvor galt det står til med den globale opvarmning i Antarktis, eller nærmere sagt i *West* Antarktis. Temperaturer ved stationer i den centrale og østlige del af Antarktis viser en nedadgående trend (nogle stationer som f.eks tyske Neumayer har optegnelser der går tilbage til 1950erne). Forfatterne i denne artikel har undersøgt om denne difference skyldes naturlige udsving, og de er kommet frem til, at den observerede opvarmning i West Antarktis er naturlig.

Ulrike: vil du dele din kilde til, at den observerede opvarmning af vest Antarktis er naturlig?
Jeg har fundet flere undersøgelser, der ikke bakker op om din påstand.

A new study has for the first time presented solid evidence that human-caused global warming is linked to melting of the West Antarctic Ice Sheet. Scientists already knew that periodically changing winds in the region have caused an increase in warm ocean conditions around key glaciers in West Antarctica, and that this is causing them to lose ice. But they did not know whether changes in the winds could be linked to global warming. The new study shows that changes in the winds have indeed been influenced in part by warming climate, along with shorter-term natural variations in climate. The findings are published today in the journal Nature Geoscience.

Satellite monitoring has shown that large areas of the West Antarctic Ice Sheet are losing ice, and that the loss has increased substantially in the last few decades. If the trend continues, the melting could cause tens of centimeters of sea-level rise by the year 2100. Scientists have known for some time that varying winds in the region cause relatively warm or cool water to be driven toward key glaciers at different times. But it has not been clear whether these swings are caused by natural climate variations, or are linked to human-induced climate change.

Peter Villadsen skrev:

Peter Villadsen skrev:
Ulrike Pielmeier fortæller i Facebook gruppen "Klimarealisterne":

Godt spottet fra Lars Brandt. Man hører ofte hvor galt det står til med den globale opvarmning i Antarktis, eller nærmere sagt i *West* Antarktis. Temperaturer ved stationer i den centrale og østlige del af Antarktis viser en nedadgående trend (nogle stationer som f.eks tyske Neumayer har optegnelser der går tilbage til 1950erne). Forfatterne i denne artikel har undersøgt om denne difference skyldes naturlige udsving, og de er kommet frem til, at den observerede opvarmning i West Antarktis er naturlig.

Ulrike: vil du dele din kilde til, at den observerede opvarmning af vest Antarktis er naturlig?
Jeg har fundet flere undersøgelser, der ikke bakker op om din påstand.

Ulrike: grunden til, at jeg ikke deltager i Facebook gruppen "Klimarealisterne" er ganske enkelt, fordi der er mere personlige antagelser end ordentligt undersøgte forhold.
Du har tidligere påstået, at du er forsker, men jeg undres da derfor meget over, at du offentligt påstår, at opvarmningen af vest Antarktis er naturlig?

Se nedenstående:

A new study has for the first time presented solid evidence that human-caused global warming is linked to melting of the West Antarctic Ice Sheet. Scientists already knew that periodically changing winds in the region have caused an increase in warm ocean conditions around key glaciers in West Antarctica, and that this is causing them to lose ice. But they did not know whether changes in the winds could be linked to global warming. The new study shows that changes in the winds have indeed been influenced in part by warming climate, along with shorter-term natural variations in climate. The findings are published today in the journal Nature Geoscience.

Satellite monitoring has shown that large areas of the West Antarctic Ice Sheet are losing ice, and that the loss has increased substantially in the last few decades. If the trend continues, the melting could cause tens of centimeters of sea-level rise by the year 2100. Scientists have known for some time that varying winds in the region cause relatively warm or cool water to be driven toward key glaciers at different times. But it has not been clear whether these swings are caused by natural climate variations, or are linked to human-induced climate change.

Altså: din påstand om at vest Antarktis opvarmning skyldes naturlige variationer er et falsum.

https://blogs.ei.columbia.edu/2019/08/12/scientists-link-climate-change-melting-west-antarctica/

The current west-east asymmetry of Antarctic surface climate change is undoubtedly of natural origin because no external factors (e.g., orbital or anthropogenic factors) contribute to the asymmetric mode.

Modern instrumental records over Antarctica are too short to illustrate the potential multidecadal natural variability in these climate modes.

Our record explains 49% of the temperature variation, and documents two major warm periods between 3140–2800BC and 70BC – 150AD, which coincide with the lack of evidence of glacier advances in SSA. Recent decades in the reconstruction (1959–2009) show a warming trend that is not exceptional in the context of the last five millennia. The long-term relationship between our temperature reconstruction and a reconstructed total solar irradiance record, with coinciding cycles at 293, 372, 432–434, 512 and 746 years, indicate a persistent influence of solar forcing on centennial climate variability in SSA. At interannual to interdecadal scales, reconstructed temperature is mainly related to the internal climate variability of the Pacific Ocean, including El Niño Southern Oscillation (ENSO) and longer oscillations. Our study reveals the need to characterize regional-scale climate variability and its drivers, which in the context of global-scale processes such as anthropogenic warming, interact to modulate local climate affecting humans and ecosystems.

The tree-ring summer temperature record presented here indicates a warming trend in southern South America since the 1960s. Nevertheless, this pattern is not unprecedented in the context of the last five millennia, during which several warm periods larger in magnitude and duration are recorded. This pattern for the last decades is in agreement with recent trends reported in instrumental temperature records that suggest that the mid-latitudes of the ocean-dominated Southern Hemisphere are not warming at the same rate as other areas in the last four decades (Falvey and Garreaud, 2009).

Ulrike Pielmeier´s påstand:

Forfatterne i denne artikel har undersøgt om denne difference skyldes naturlige udsving, og de er kommet frem til, at den observerede opvarmning i West Antarktis er naturlig.

Peter Villadsen skrev:
Ulrike, hvor i dit materiale står der, at opvarmningen af vest Antarktis skyldes naturlige variationer (din påstand)?

[quote]Ulrike Pielmeier´s påstand:

Forfatterne i denne artikel har undersøgt om denne difference skyldes naturlige udsving, og de er kommet frem til, at den observerede opvarmning i West Antarktis er naturlig.

Although multiple mechanisms, including both forced and
natural origins, contribute to the west-east asymmetry of Antarctic
climate change in complicated ways, this pattern should primarily
be manifested through internal factors within Antarctica. On the
basis of this idea, we aim to prove that the asymmetry of the temperature
trend comes from the robust high-latitude mode of
multidecadal natural variability, inducing inverse temperature anomalies
between the two subcontinents that internally originate in and
around Antarctica. Here, "internal origin" implies that the phenomenon
originates primarily from high latitudes, combined with
WAIS-EAIS topographical distinction and winter amplification of
the atmospheric dynamical response to multidecadal SST variability
in the Amundsen-Bellingshausen seas (ABS) (20–22).

From these experiments, we can deduce the role of the Antarctic
topographic layout in controlling the tropospheric circulation and
consequent SAT variation over Antarctica. The current lower West
Antarctic terrain allows warm air to be advected from the Amundsen-Ross
seas to West Antarctica, while the steep TAM hinders warm
air from flowing toward East Antarctica. Across the heated West
Antarctic coastal region, the barotropic anticyclone system develops,
which can reinforce warm advection from the Amundsen-Ross seas
(Fig. 5, D and E). The heat transport by synoptic eddy activity over
the west Antarctic coastal region contributes to reinforcement in
warm air advection (36), and the contribution of synoptic eddy
activity could increase under the flattened Antarctic topography
(37). In addition, the anticyclone system also enforces southward
meridional oceanic flow over the ABS by Ekman transport, which
supplies warm water from the extratropics to these seas (Fig. 5,
G and H). Eventually, the warmer land surface, the development
of the anticyclone system, and the warmer ocean surface together. strengthen the warming over West Antarctica by promoting each
other

The consistency
between the observation and models over the high-latitude ocean
enables us to think it reasonable to argue the harmony of the
atmosphere-ocean coupled feedback off West Antarctica and the
Antarctic terrain to generate the Antarctic west-east asymmetric
natural variability.

In the asymmetric mode of Antarctic SATs, multidecadal
variability is found in the long paleoclimate datasets of PAGES
Antarctica2k, LOVECLIM, and TraCE-21K. This suggests that the
enhanced asymmetric trend between West and East Antarctica
during recent decades could be a manifestation of multidecadal
variability.

Jørgen Petersen skrev:
Som bekendt er der risici ved næsten alt. Eksempelvis er det livsfarligt at færdes i trafikken. Så vidt jeg husker, er der omkring 200 mennesker som bare i vores lille land mister livet i trafikken hvert år.

Det afgørende er derfor håndteringen af disse risici. I relation til GW er problemet, at risiciene og problemerne herved systematisk er blevet blæst op af diverse skræmmekampagner. Derfor er det fuldt ud relevant at skelne skarpt imellem harmløs global opvarmning (som samlet set er en fordel) også katastrofal global opvarmning.

Jørgen Petersen skrev:
IPCC og den såkaldte klimaforskning lever af folks angst for GW med mere. Derfor er der ingen grund til at læse alle disse skræmmerapporter.

Så let som ingen ting kan man således lave en lang liste over forhold, hvor de beviseligt har lavet vilde overdrivelser, uden at de vil trække disse overdrivelser tilbage. Her kan eksempelvis nævnes:

Påstandene om den alarmerende afsmeltningen af indlandsisen på Grønland.
Påstandene om den faretruende afsmeltning af havisen ved Nordpolen.
Påstandene om ophøret af Golfstrømmen.
Påstandene om en negativ indvirkning på planteavlen ved GW.
Påstandene om mere ekstremt vejr p.g.a. GW
OSV.

Top, Antarctica as seen from space with illustration of mechanisms discussed by Clem and colleagues9. Stronger westerlies driven by warming, combined with tropical teleconnections from the negative phase of the Interdecadal Pacific Oscillation, produce enhanced cyclonic activity in the Weddell Sea (dark blue arrows). This increases the advection of warm moist air into the high Antarctic interior (red arrows), but shifts wind direction over the Peninsula, slowing the warming there. Bottom, mean annual air temperatures at Faraday/Vernadsky Station and the South Pole (locations shown in top image). Near-record lows (1983, 1987, 1993, 1997 and 1999) and highs (2002, 2005, 2009, 2013 and 2018) are identified in the South Pole series with blue and red squares, respectively

Peder Kruse skrev:
Local Warming ?

"Theory suggests that this is occurring because, without ice sheets on top of them, there is a release of pressure on the regions' volcanoes and they become more active."

And this could happen in west Antarctica, where significant warming in the region caused by climate change has begun to affect its ice sheets. If they are reduced significantly, this could release pressure on the volcanoes that lie below and lead to eruptions that could further destabilise the ice sheets and enhance sea level rises that are already affecting our oceans.

"It is something we will have to watch closely," Bingham said.

Peder Kruse skrev:
To panic or not to panic

Ja, når bare en af dem går i udbrud, så stiger problemerne blot for hele menneskeheden

When atmospheric carbon dioxide is above about 300 parts per million, the infrared warming effect is so strong it drowns out the more subtle Milankovitch cycles and there are no ice ages. Coming out of the Pliocene period just under three million years ago, carbon dioxide levels dropped low enough for the ice age cycles to commence.

Now, carbon dioxide levels are over 400 parts per million and are likely to stay there for thousands of years, so the next ice age is postponed for a very long time. We will be living in a warmed and changed climate for many generations to come.

In a study accepted for publication in the journal Geophysical Research Letters, a research team led by Zeke Hausfather of the University of California, Berkeley, conducted a systematic evaluation of the performance of past climate models. The team compared 17 increasingly sophisticated model projections of global average temperature developed between 1970 and 2007, including some originally developed by NASA, with actual changes in global temperature observed through the end of 2017. The observational temperature data came from multiple sources, including NASA's Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP) time series, an estimate of global surface temperature change.

The results: 10 of the model projections closely matched observations. Moreover, after accounting for differences between modeled and actual changes in atmospheric carbon dioxide and other factors that drive climate, the number increased to 14. The authors found no evidence that the climate models evaluated either systematically overestimated or underestimated warming over the period of their projections.

Peter Villadsen skrev:
De modeller, der forudsiger de globale temperaturer, viser temperaturstigninger, der er i overensstemmelse med det målte.
Der er desværre en del forvirring omkring dette emne, og nogle tror, at modellerne ikke passer.
Det er forkert.
]

Peder Kruse skrev:

Peter Villadsen skrev:
De modeller, der forudsiger de globale temperaturer, viser temperaturstigninger, der er i overensstemmelse med det målte.
Der er desværre en del forvirring omkring dette emne, og nogle tror, at modellerne ikke passer.
Det er forkert.
]

Forvirringen er helt på Peter Villadsens side