| Popis: |
Using the 44-yr (1958~2001) dataset provided by ECMWF and the parameterization method, the spatial-temporal distribution of ozone amount in the 6-km layer near the tropopause and the heating rate are calculated. The results show that: (1) the spatial gradient of ozone distribution is from equatorial to polar regions, while the spatial gradient of the heating rate distribution is from the high-latitude and low-latitude to the subtropics. It is likely that such meridional gradient is an important factor which drives the tropopause structure variations. The seasonal variation of the spatial distributions of ozone amount and heating rate is obvious, while they are not fully consistent with each other. The spatial structure in January and April is reverse with that in July and October and abrupt change exists along with season varying. The seasonal change is relatively stable in East Asia and the Qinghai-Tibet Plateau. (2) The heating rate and ozone amount shows positive correlation in the areas controlled by tropopause in tropics, and the relationship varies with seasons in the areas controlled by the polar tropopause. Also this relationship has something to do with the declination; there exists phase of seasonal variation and the variability among the different latitudes, while it is more consistent in Southern Hemisphere, the largest anomaly is ±2 × 10−4 K·d−1. And it is more complex in Northern Hemisphere, the largest positive anomaly is ±4 × 10−4 K·d−1. The seasonal phases are generally reverse in two Hemispheres. (3) The seasonal variation phase of ozone amount anomaly exceeds that of heating rate anomaly by 2~3 months in the period of seasonal adjustment, except in the equatorial areas; The largest anomaly is greater than 0.4 DU in August in Antarctic, and smaller than –0.2 DU in March and April; and it is ±0.2 DU in Arctic. (4) The interannual and interdecadal evolution of ozone amount and heating rate are correspondent, both show multi-scale structure characteristics. The differences of spatial-temporal evolutions between the two Hemisphere and equatorial areas are obvious. The amplitude of heating rate in the areas between 30°S~30°N is rather dramatic, and the largest anomaly is ±2.5×10−4 K·d−1, the amplitude in high- latitude and pole in two hemisphere is different in different periods; while the amplitude of ozone amount shows reverse characteristics. The largest anomaly is greater than 0.25 DU or smaller than –0.35 DU in Arctic areas. (5) There are opposite anomaly structures in two Hemispheres before 70's and mid-70's in 20th century, while the most remarkable period of the minus anomaly is in 90's. |
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