Measurements of the Diurnal Warm Layer and Biologically-Induced Heating during the CIRENE Campaign

印度洋的大气对流对季风有很强的影响。在冬季，对流的最大振幅位于赤道和20 S之间，通常被称为Madden-Julian振荡（MJO）。最近基于卫星数据的研究表明，该地区的季节内活动与大的海表温度（SST）变率（高达3 ℃）有关，并认为海气相互作用起着重要作用。迄今为止，只有卫星数据和数值模型用于调查这些区域的变化。建议参加法国的一项运动，其目的是了解印度洋这一区域季节内时间尺度上的海洋-大气耦合，并解释SST变率的机制及其对大气演变的影响。测量将使用海气相互作用剖面仪（ASIP）进行，该剖面仪增加了5个拉格朗日浮标，并附有24个节点的温度链。ASIP以前由NSF海洋学技术方案资助，将以亚厘米的空间分辨率和5分钟的重复间隔提供混合层整个深度的温度、电导率、切变、荧光/浊度和PAR的剖面。这一建议将解决以下基本问题：1。局部SST条件和暖层的日循环与大尺度大气条件的相对重要性2.生物对近地层热捕获的贡献及其在总热收支中的作用。这些目标的更广泛影响涉及气候变化，解决了与印度洋大气对流有关的一些问题; MJO与厄尔尼诺-南方涛动、季风和热带外天气相互作用，因此具有全球重要性。

Atmospheric convection in the Indian Ocean has a strong impact on the monsoon. During winter, the maximum amplitude of convection is located between the equator and 20 S, and is generally referred to as the Madden-Julian oscillation (MJO). Recent studies based on satellite data have shown that the intraseasonal activity in this region is associated with large sea surface temperature (SST) variability (up to 3 C), and it has been suggested that air-sea interaction plays an important role. Heretofore there have been only satellite data and numerical modelling used to investigate the variability in these regions. It is proposed to participate in a French Campaign the objective of which is to understand ocean-atmosphere coupling at the intraseasonal timescale in this region of the Indian Ocean, and to explain the mechanisms of the SST variability and its influence on the atmospheric evolution. Measurements will be made using the Air-Sea Interaction Profiler (ASIP), augmented with 5 Lagrangian floats, with 24-node temperature chains attached. ASIP, previsouly funded by the NSF Oceanographic Technology program, will provide profiles of temperature, conductivity, shear, fluorescence/turbidity, and PAR over the full depth of the mixed layer at sub-centimeter spatial resolution and repeat intervals of 5 minutes. This proposal will address the following fundamental problems: 1. the relative importance of local SST conditions and the diurnal cycle of the warm layer versus large scale atmospheric conditions 2. the biological contribution to heat trapping in the near-surface layer, and its role in the overall heat budget. The broader impacts of the objectives relate to climate change by addressing some of the issues pertinent to atmospheric convection in the Indian Ocean; the MJO interacts with the El Nino-Southern Oscillation, the monsoons, and extratropical weather, and therefore of global importance.