Conference Agenda

A large number of studies explored the mechanisms of synoptic-scale forming of ozone mini holes/highs: far-range meridional transport of air masses from regions with different climatological ozone mixing ratios (called “mechanism A”) and adiabatic vertical displacement of isentropes (mechanism B). In the paper, we investigate ozone mini holes/highs events over the North China Plain in winter during 1979-2019. The analysis shows that most ozone mini holes/highs events conform to the mechanism A and B and two typical weather change processes accompanying with these events: rapid cooling weather processes accompanies with ozone minihighs, while abnormal rapid warming weather processes accompanies with ozone miniholes. However, we also find a significant proportion of anomalous events do not conform to this rule: rapid cooling processes accompanies with ozone minihighs, while rapid warming processes accompanies with ozone minihighs. Behind these abnormal phenomena, there may exists a new ozone mini holes/highs forming mechanism: rapid cooling weather processes accompanies with ozone miniholes, while abnormal warming weather processes accompanies with ozone minihighs. The new mechanism may be related to the land and sea position of the North China Plain in the east and its landform features in the west.

ID: 59376/DRAGON 5
Title: Pacific modulation of the Sea level variability in the Arctic Ocean and Nordic Seas.

It is crucial to monitor and understand regional sea-level changes that can differ from Global Mean Sea Level (GMSL) both in terms of magnitude as well as governing forcing and mechanisms (Stammer et al., 2013). For instance, while changes in salinity can have significant distinct impact on regional sea level change, such as in the Arctic Ocean, it has minor effect on GMSL. Quantifying the natural variability in the regional sea level change is also urgent in order to distinguish it from a potentially forced (anthropogenic) signal. Furthermore, the role of remote impact of climate variability in one region on the other needs to be well-understood. Climate change in the Pacific can, for instance, impact Arctic warming and the sea ice (Li et al., 2015; Svendsen et al., 2018; Yang et al., 2020). How this translates to sea level change remains unclear. The aim of this study is to examine and relate the sea level variability of the Beaufort Gyre (BG) in the Arctic Ocean to natural climate variability of the Pacific Ocean.

In so doing, results of three distinct analyses are reported here: (i) The variability of the BG as estimated using the state-of-the-art ESA Cryo-TEMPO altimeter data, while freshwater content estimates are derived from in-situ observations, ocean reanalysis and satellite sea surface salinity, satellite altimeter and gradiometer data; (ii) The benefits of the reprocessed altimetry dataset at 5 Hz with augmented signal resolution to study the mesoscale-based sea level variability of the Arctic and Nordic Seas; (iii) The usefulness of estimating a Multiparameter Eddy Significant Index in the Nordic Seas; and (iv) The remarkable role of North Pacific Oscillation in the Beaufort Sea level change.

龙计划5 ID：59376
题目：太平洋气候系统对北冰洋和北欧海海平面变化的影响

监测和理解区域海平面变化极为重要。区域海平面变化的幅度以及影响因子和机制方面均有别于全球海平面的变化（Stammer等，2013）。例如，盐度变化在北冰洋海平面的变化中具有重要作用，但其对全球海平面变化的影响则很小。定量研究区域海平面变化对自然变率和人为强迫的响应具有重要意义。此外，一个地区的气候变化对另一个地区的远距离影响需要深入探究。例如，太平洋气候系统变化可以影响北极地区的气候变化（Li等，2015；Svendsen等，2018；Yang等，2020）。然而，太平洋气候变化如何影响北冰洋的海平面变化尚不明晰。本研究旨在探究波弗特海的海平面变化与太平洋气候系统之间的联系。

本次报告主要介绍四项相关的研究内容：（1）利用先进的ESA Cryo-TEMPO高度计数据估算波弗特海平面的变化，其中数据来自于实地观测、海洋再分析、卫星海表盐度、卫星高度计和梯度计；（2）重新处理的z具有增强信号分辨率的5 Hz下的高度计数据，用于研究北冰洋和北欧海域的中尺度海平面变化；（3）在北欧海域估算多参数涡度显著指数的作用；（4）北太平洋涛动模态可以显著影响波弗特海平面变化