Sentences with phrase «century warmth»

So stats won't help us solve this problem of 20th century warmth in the context of the last few centuries.

Most of the reconstructions indicate late 20th century warmth that is unprecedented over the past 1000 years, without any consideration of the instrumental record.

The report states: «The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1000 years.

Here's figure 5 that tells the story: Look at graph 5c, and you'll see 20th century warmth matches peaks either side of the year...

In order to preclude a Quebec composite from indicating a potentially unrealistic magnitude of late 20th century warmth for the whole region, we created a shorter composite of the four sites that averages records from a Fort Chino and No Name Lake composite after 1806.

Indeed, we are able to reproduce the MM reconstruction of anomalous 15th century warmth when the entire ITRDB North American data set (and the «Queen Anne» series) are censored from the proxy network (Figure 4).

This is what Osborn and Briffa have done in their article «The Spatial Extent of 20th Century Warmth in the Context of the Past 1200 Years», which appears in the Feb 10 issue of the journal Science.

Indeed, the bizarre resulting claim by MM of anomalous 15th century warmth (which falls within the heart of the «Little Ice Age») is at odds with not only the MBH98 reconstruction, but, in fact the roughly dozen other estimates now published that agree with MBH98 within estimated uncertainties.

So how has Monckton managed to take this straightforward data from Thompson et al (2003) whose conclusion concerning their «low latitude D18O history for the last millennium» is that in low latitudes (as judged by a composite ice core oxygen isotope enrichment analysis as a temperature proxy), the temperature has followed a pattern similar to that of the NH reconstructions with a little bit of a MWP, a small LIA and a very large late 20th century warmth...

The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years.

The conclusion is not especially surprising, as nearly all previous peer - reviewed studies over the past decade find that late 20th century warmth is anomalous in a millennial or longer context.

The article uses a rigorous statistical methodology to re-examine the question of whether late 20th century warmth is anomalous in the context of the past 1200 years.

Mann, M.E., Ammann, C.M., Bradley, R.S., Briffa, K.R., Crowley, T.J., Hughes, M.K., Jones, P.D., Oppenheimer, M., Osborn, T.J., Overpeck, J.T., Rutherford, S., Trenberth, K.E., Wigley, T.M.L., On Past Temperatures and Anomalous Late 20th Century Warmth, Eos, 84, 256 - 258, 2003.

There are numerous periods (Figure 1d) of one or two decades with relatively high growth (and inferred summer temperatures close to the 1961 - 90 level) but at longer timescales (Figures 1e and 1f) only the 40 - year period centred at 250 CE appears comparable with 20th century warmth.

Of course, in the real world, the 1880's where exceptionaly cold, peak 20th century warmth was in the 1990's (which in turn were cooler than the first decade of the 21st century), and the 1970's and following decades were characterised by an ongoing rise in temperatures.

Bürger G., (2007) Comment on the Spatial Extent of 20th - Century Warmth in the Context of the Past 1200 Years, Science, 316/5833, 1844.

«On Past Temperatures and Anomalous Late - 20th Century Warmth.»

Hence the conclusion of unique late 20th century warmth is not robust — in other word it does not hold up under minor variations in data or methods.

The warmest 30 - year period was A.D. 21 - 50, which was 1.05 °C warmer than the mean temperature for 1951 - 1980 and ~ 0.5 °C warmer than the region's maximum 20th century warmth, which occured during 1921 - 1950.

The hockey stick instantly became the poster child for pro-Kyoto advocacy, touted as seeing - is - believing evidence that late 20th century warmth was unprecedented during the past 1,000 years, and that mankind's fuelish ways must be to blame.

«The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years.

Soon, W., S. Baliunas, and D.R. Legates, 2003: Comment on AOn past temperature and anomalous late ‑ 20th Century warmth» by Mann et al., Eos 84 (44): 473.

On past temperatures and anomalous late 20th century warmth.

I typed out the section of BO2001 where they explicitly said the earlier reconstructions, like B1998a (the paper referred to, with the Phil Trans paper, as the source by BO99) are of limited use for judging the relative magnitude of 20th century warmth.

Of course, if the MWP was shown to be global in extent and as warm or warmer than today, then obviously the late 20th Century warmth would not be unprecedented.

Severinghaus asked about the «flat» response of tree rings to late 20th century warmth, referring to an article by Briffa and Osborn in Science (2002).

To define medieval warmth in a way that has more relevance for exploring the magnitude and causes of recent large - scale warming, widespread and continuous palaeoclimatic evidence must be assimilated in a homogeneous way and scaled against recent measured temperatures to allow a meaningful quantitative comparison against 20th - century warmth (Figure 6.10).

The weight of current multi-proxy evidence, therefore, suggests greater 20th - century warmth, in comparison with temperature levels of the previous 400 years, than was shown in the TAR.

Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales.