Sentences with phrase «even the temperature reconstructions»

Even the temperature reconstructions that show the greatest variations in the past 1000 years suggest up until the 1980s, average temperature changes remained within a narrow band spanning 1ºC at most.

Not exact matches

Incidentally, as I see it, your reconstruction of Manns data showing the 15th century to be warmer than now is even more damming than Manns original construct, as it indicates a gradual decline in global temperatures until 1850, before human influence reversed that trend.

There are alternatives to our proposition of a -0.2 K temperature offset — which seems a bit large against the apparent quality of this reconstruction, even this far back — but they would be speculative at this point.

As far as this historic period is concerned, the reconstruction of past temperatures based on deep boreholes in deep permafrost is one of the best past temperature proxies we have (for the global regions with permafrost — polar regions and mountainous regions)-- as a signal of average temperatures it's even more accurate than historic direct measurements of the air temperature, since the earth's upper crust acts as a near perfect conservator of past temperatures — given that no water circulation takes place, which is precisely the case in permafrost where by definition the water is frozen.

Surface temperatures in parts of Europe appear to have have averaged nearly 1 °C below the 20th century mean during multidecadal intervals of the late 16th and late 17th century (and with even more extreme coolness for individual years), though most reconstructions indicate less than 0.5 °C cooling relative to 20th century mean conditions for the Northern Hemisphere as a whole.

Even putting aside the OHC data and fingerprinting, there is absolutely no evidence in model simulations (or in prevailing reconstructions of the Holocene), that an unforced climate would exhibit half - century timescale global temperature swings of order ~ 1 C. I don't see a good theoretical reason why this should be the case, but since Judith lives on «planet observations» it should be a pause for thought.

In mid-20th Century, medieval temperatures are exceeded in all the reconstructions, hence recent (last 10 - 15 years, say) temperatures appear to be unprecedented for at least a millennium (that even holds for the alternative histories presented by the «hockey stick» critics).

They have not even cited the ACRIM satellite reconstruction that shows a significant slow variation of the temperature since 1978 (They have shown only the PMOD composite, and I can ensure you those people know quite well about the existence of the ACRIM composite).

But even if the secular trend of solar is reduced in more recent estimates, that only means that the pre-industrial fit of the temperature reconstructions needs a larger factor for solar...

The current rise in temperatures is still anomalous and more rapid than anything seen in any other time period of any of the reconstructions (even the statistically bad ones of M&M).

And there are a whole load of other temperature reconstructions that M&M haven't even addressed.

BTW, the authors continue considering both the LIA and the MWP as valid concepts, contrary to Mann et al. 2) Even though they have little confidence in temperature reconstructions previous to AD 1600 and very little for those previous to AD 900, the authors consider that Mann et al's claim of the last decades being warmer than any such period in the past millennium is nonetheless plausible.

I think the AGW problem is actually more serious if the natural variability is as large as more recent paleoclimate reconstructions suggest: Not only do you have significant temperature swings, you can't even predict them.

I also note that I have had a shot at the hockey stick at the basic level of whether tree rings are even valid as a proxy for long term temperature reconstruction (Loehle, C. 2004.

Current temperatures are higher than in the last 1000 years, even in temperature reconstructions with the strongest MWP (such as Loehle).

3) Lamb's temperature reconstruction These are things come to mind quickly, I am sure I could come up with even more if I wanted to think about longer.

It should be: Climate scientists doing temperature reconstructions do not even go that far.

Climate scientists wormy in the sea of temperature reconstructions do not even go that far.

I'm surprised that scientist are ignoring satellite reconstruction with higher tropical trends compared to regularly updated uah, rss timeseries; indeed if Zou et al. approach turn out to be correct not only the discrepancy between satellite reconstruction and models does not exist but even papers like Klotzbach et al. claiming that the discrepancy is due to biases in the surface temperature record would be wrong.

Along the way, Corcoran even manages to confuse a little known Phil Jones graphic with Michael Mann's «hockey stick» millenial temperature reconstruction.

Lacking valid SCIENCE «temperature reconstruction» can only remain a concept, as a THEORY requires valid construction, which even the «Greenhouse Theory» does NOT have, and it is NOT sufficient to cite «validation» of that theory incorporated as the USE of such needs Theory also requires to REMAIN valid.

The Hockey stick in this paper doesn't even preclude the possibility of a Medieval Warm Period with about equal temperatures as in the 20th century, since the 20th century average temperature still lies within the upper half of the error band of Mann's Hockey Stick in the part of the reconstruction that covers the Medieval times.

We can also step back even further and compare the projected temperature change over the next century to reconstructions over the past 1,500 years:

Many reconstructions show temperatures during the Medieval and Roman periods were warmer than the present, and this study suggests they were even warmer than previously thought»

Mann even showed the same hockey stick pattern * without * the tree ring proxies that some people had objected to: «Proxy - based reconstructions of hemispheric and global surface temperature variations over the past two millennia»

Even if we accept the questionable assumption that meteorite clusters give information on CRF variations, we find that the evidence for a link between CRF and climate amounts to little more than a similarity in the average periods of the CRF variations and a heavily smoothed temperature reconstruction.

If, as I understand it, reconstructions of temperatures from the end of the 19th century through the mid 20th century are done using a combination of the few hard records available and proxy estimation you have an even more fundamental flaw.

Regionally, there may have been places that exhibited notable warmth — Europe, for example — but all global proxy reconstructions agree it is warmer now, and the temperature is rising faster now, than at any time in the last one or even two thousand years.

Even with the generally large spatial coherence and correlation length scales of temperature anomalies at polar latitudes (e.g. Hansen et al. 1999; Chapman and Walsh 2007), none of the reconstruction methods can escape the basic limitation of few in situ observations in West Antarctica, and all exhibit less skill in this region compared with other regions of the continent.

Mann even showed the same hockey stick pattern * without * the tree ring proxies that many people had objected to: «Proxy - based reconstructions of hemispheric and global surface temperature variations over the past two millennia»

Other specialists e.g. Briffa, Cook clearly understood that, despite Mann's claims to have achieved a hemispheric (and even global) temperature reconstruction, Mann's network did not actually contain qualifying information from the NH tropics — nor did the other AR4 reconstructions.

In fact, the assumed 60 year cycle which was the basis of the L&S model doesn't even show up in Loehle's own millennial global temperature reconstruction - a glaring contradiction.

And as we saw in Figures 2 and 3, their assumed 60 year cycle does not show up in millennial temperature reconstructions - not even in Loehle's own previous work!

... Tamino has done some good work to demonstrate that a spike the likes of we've seen recently in the temperature record, even in a grid resolution of 100 - 300 years, might still likely have been caught in the reconstruction, and that if there could have been such a spike posited it would have to come with some physical basis.

Even though lauded as a very valuable and novel contribution to the field, Snyder's reconstruction has also been criticized because the temperature amplitude between glacial and interglacial states appears relatively large (~ 6 degrees) compared to other recent reconstructions, e.g. by Shakun et al (2012)(~ 4 degrees).

True in the sense that even though the average temperature reconstruction «makes sense» there is zero formal error estimation of either the interpolation error of the global surface temperature reconstruction, or the quadrature thereof and hence the uncertainty in the temperature record is completely unknown (save maybe sound extreme bounds that one could probably work out on a napkin).

Frankly, after this exhaustive (and exhausting) examination of Section 3, I'm sure readers will understand (and even be grateful) if I do not enter a detailed discussion of Section 4, which contains an actual temperature reconstruction.

Even with these weaknesses in obtaining reasonable proxies for temperature reconstructions, I seldom or never see papers by climate scientists that even consider cross validations of any sophisticatEven with these weaknesses in obtaining reasonable proxies for temperature reconstructions, I seldom or never see papers by climate scientists that even consider cross validations of any sophisticateven consider cross validations of any sophistication.

Because if you don't believe the instrumental temperature record, then why even bother to attempt a very much less accurate method of reconstruction, where the error bars are most likely larger than the reconstructed time series itself?

But it was cold this winter and C02 is plant food and only a trace gas and the greenhouse effect has been disproved anyway and even if the greenhouse effect does exist, C02 has negligible impact compared to water vapour and our only source of heat is the sun so it must be the sun, unless it is due to the C02 from volcanoes, but C02 follows warming so it can't be the C02 and the medieval warm period was warmer anyway and all the temperature reconstructions that show this not to be true are produced by corrupt scientists being paid by corrupt governments that have colluded to create an excuse to form a one world unelected social - ist government and even if the scientists are not that corrupt, although the e-mails prove they are, they have still got it wrong as the climate sensitivity is not as high as they think it is because it is basically the planets orbits and cosmic rays so we can say for a fact that the warming that probably does not exist is definatley not due to humans and even if it was the evidence is not sufficient to make drastic changes to the economy and increase taxes so that the politicians and scientists and business leaders get rich and leave us all poor — do they think we are stupid or something?

Mann et al. (2008) narrowed the band of uncertainty with detailed reconstructions, finding a Northern Hemisphere medieval warm period, but with post-1980s temperatures clearly higher even if they excluded data from tree rings (the main point where critics had attacked).

If this component is used by itself or in conjunction with a small number of unaffected components to perform reconstruction, the resulting temperature reconstruction may exhibit a trend, even though the individual proxies do not.

However, even by 1900, reconstructions of hemispheric temperatures show evidence for a detectible warming driven by increases in greenhouse gases, particularly relative to slightly reduced CO2 during the Little Ice Age (Abramet al., 2016; Schurer et al., 2013) consistent with attribution of a substantial fraction of the ETCW in temperature reconstructions to greenhouse gas increases (Schurer et al., 2013).

Using instead the 4.0 + / -0.8 C warming estimate from the Annan and Hargreaves (2013; doi: 10.5194 / cp -9-367-2013) global reconstruction of temperature changes at the LGM implies an even lower ECS best estimate, of 1.56 C.

Eric did not state that explicitly, but he does mention that you reconstructed a temperature trend for Byrd which is +0.08 C / decade, while for example the Monaghan et al 2008 reconstruction for Byrd comes out at +0.32 C / decade, and the updated Monaghan estimate indicates an even higher trend (> 0.4 C / decade).