Sentences with word «kyr»

Figure 3: The phasing of CO2 concentration and temperature for the global (grey), Northern Hemisphere (NH; blue) and Southern Hemisphere (SH; red) proxy stacks based on lag correlations from 20 — 10 kyr ago in 1,000 Monte Carlo simulations.

«Finally, if we are correct that the 1 - 2 kyr cycle is a persistent feature of climate, at least in the North Atlantic, then one conclusion seems inescapable.

The first column is time before present in kyrs, the second, Earth orbit semi-major axis.

These data suggest that ENSO variability was weaker than today prior to approximately 5 kyr before present (Moy et al., 2002 and references therein; Tudhope and Collins, 2003).

The causes of the age differences at MIS 5 were proposed to occur from (i) an overestimation of the surface mass balance at around MIS 5d - 6 in the glaciological model, and (ii) an error in one of the age constraints by ~ 3 kyr at MIS 5b.

Averages over 3, 7 and 10 kyrs from the CALSxk models (Figs. 2b — 2d) suggest that, although there are zonal differences of minimum field intensity, the southern Atlantic is no preferred location for the minimum field strength.

High - frequency variations (black) are five - point running means of the original data [4], whereas the blue curve has a 500 kyr resolution.

East African hominin diversity at each 100 kyrs interval were estimated using first (FAD) and last appearance dates (FAD) from the literature [2], [35]--[36], [46].

The 8.2 kyr Holocene thermal maximum is thought to have been buffered by the presence of the Laurentide ice sheet in the northern hemisphere.

It uses sliding window averages of width 500 years shifted by 100 years back to 2000 BC and 1 kyr shifted by 500 years back to 10000 BC.

«The evidence currently available indicates that NH mean temperatures during medieval times (950-1100) were indeed warm in a 2 - kyr context and even warmer in relation to the less sparse but still limited evidence of widespread average cool conditions in the 17th century (Osborn and Briffa, 2006).

We used the FAD and LAD to generate estimates of hominin diversity during each 100 kyrs block between the present and 3 Ma.

The lake variability index was calculated by collating the published geological evidence for the appearance of either deep ephemeral or shallow alkaline lakes in seven major Basins in 50 kyrs sections over the last 5 Myrs [15], [17], [23]--[27], [34]--[37].

The 14C ages were corrected for mass - dependent fractionation with measured δ13C values, 33 and compared with samples of Pleistocene whale bone or calcite (backgrounds, > 48 14C kyr BP), late Holocene bison bone (∼ 1,850 14C BP), late AD 1800s cow bone and OX - 2 oxalic acid standards for calibration.

It took on the order of 100 kyr for the oxygen and carbon isotopic signals in the ocean to return to their original steady - state values after the PETM.

The CaCO3 cycle was able to keep up with the 10 - kyr CO2 rise as the ice sheets melted, but it won't be able to keep up with the 100 - yr anthropogenic CO2 rise.

The carbon release of 4500 to 6800 PgC over 5 to 20 kyr translates into a rate of emissions of ~ 0.5 to 1.0 PgC yr — 1 (Panchuk et al., 2008; Zeebe et al., 2009).

The last 20 kyr includes the end of the last ice age, which was indeed a large change, but as you note, rather slow.

The early Holocene CO2 trend has also been detected in a record of Betula leaves from Denmark where, in addition to the Preboreal Oscillation, younger cooling events at 7.2, 3.4, and 2.5 kyr also correlate with lowered CO2concentrations (7).

The analysis of the past 1 kyr focuses mainly on the climate response to natural forcings (changes in solar radiation and volcanism) and on the role of anthropogenic forcing during the most recent part of the record.

Older ice is required to test hypotheses about any consistent long - term CO2 trend and a probable connection with the 500 - kyr variations of the Quaternary carbon cycle found in marine records15.

The 41 kyr world: Milankovitch's other unsolved mystery.

This issue, known as the 100 - kyr problem, is compounded by a lack of explanation for the transition of the length of the cycles from 41,000 to 100,000 years at the mid-Pleistocene transition 1.2 million years ago.

The simultaneous increase in energy content of all the major components of the climate system and the pattern and amplitude of warming in the different components, together with evidence that the second half of the 20th century was likely the warmest in 1.3 kyr indicate that the cause of the warming is extremely unlikely to be the result of internal processes alone.

As the 10 kyr model, it is dominated by sediment data prior to 1000 BC.

The global field reconstructions of the CALSxk series (Continuous models based on Archeomagnetic and Lake Sediment data spanning the past x kyrs) are regularised spherical harmonic models.

The 14C curve shows an apparent phase shift during the past 5 kyr compared to all other reconstructions, which could be attributed to relatively small long - term changes in the carbon cycle during the Holocene (Muscheler et al. 2004) or that our carbon cycle model is not well calibrated to investigate 14C changes on very long time scales.

[Response: If what you said about interglaical length was true, then this one would be different in that its lasted more than 10 kyr already — William]