DEFEND FOR THE POOR CARBON
|2.0 Antarctic Ice Core Data|
|5.0 Heat Balance Mechanism||6.0 Further Interpretation of Ice Core Data||7.0 Coming Interglacial Peak Period|
2.0 ANTARCTIC ICE CORE DATA
There are few ice core data were published. The two major data are the Vostok and EPICA Dome C Ice Core data. Figure 2.1 below shows the data collected for EPICA Ice Core, each cycle from peak to peak represents the interglacial cycle.
Figure 2.1 Ė The EPICA Come C Ice Core data shows the historical record of Deuterium back to 740,000 years before present. Each peak indicates the interglacial warm period.
In June of 1999 the latest ice core data from the Vostok site in Antarctica were published by Petit et al in the British journal Nature. These new data extended the historical record of temperature variations and atmospheric concentrations of CO2, methane and other Green House Gases (GHG) back to 420,000 years before present (BP). The ice cores were drilled to over 3,600 meters. This is just over 2.2 miles deep. The analysis result is shown in figure 2.2 below.
Figure 2.2 - Graph of CO2 (green), reconstructed temperature (blue) and dust (red) from the Vostok ice core for the past 420,000 years. The Antarctic Vostok ice core provided compelling evidence of the nature of climate, and of climate feedbacks, over the past 420,000 years.
The main significance of the new data lies in the high correlation between GHG concentrations and temperature variations over 420,000 years and through four glacial cycles. However, because of the difficulty in precisely dating the air and water (ice) samples, it is still unknown whether GHG concentration increases precede and cause temperature increases, or vice versa or whether they increase synchronously. It's also unknown how much of the historical temperature changes have been due to GHGs.
Refer to figure 2.1, which is a deep ice core from EPICA Dome C, Antarctica that provides a climate record for the past 740,000 years. For the four most recent glacial cycles, the data agree well with the record from Vostok. The earlier period, between 740,000 and 430,000 years ago, was characterized by less pronounced warmth in interglacial periods in Antarctica, but a higher proportion of each cycle was spent in the warm mode. The transition from glacial to interglacial conditions about 430,000 years ago, reflects the transition into the present interglacial period in terms of the magnitude of change in temperatures and carbon dioxide level, but there are significant differences in the patterns of change. Given the similarities between this earlier warm period and today, the results may imply that without human intervention, a climate similar to the present one would extend well into the future.
The history of human began from 10,000 years ago and human civilization started from 4,000 years ago. Before that, without humanís activities, the carbon dioxide level in atmosphere varies in accordance to the temperature change.
How the carbon increase and decrease without humanís activities? In fact, the vast areas of land forests should have effect in balancing the carbon dioxide level. The possible reason is the amount of carbon dioxide was present on the earth far beyond the period shown in EPICA Ice Core data. The variation of carbon dioxide in the atmosphere is depending on the precipitation, ocean temperature and melting of ices and glaciers. When the temperature cools down, carbon dioxide in the air dissolves in the precipitation and is stored in ocean, ices and glaciers. When temperature rises, the ocean is heated up, ices and glaciers melt, the stored carbon dioxide is released to the atmosphere.
It is not the opposite way that the increase of carbon dioxide level causes the increase of atmosphere temperature.
| Main page |
This website is originated on 8-April-2010,
updated on 27-April-2010.
Copyright © 2010 by Kok-Haw Kong
All rights reserved.