Aviation Noise Monitoring Plan and datasets 2021-2022

The Australian Antarctic Division’s (AAD’s) Aviation Noise and Wildlife Monitoring Program (the Program) was established in 2021 to assess the efficacy of mitigation measures outlined in Environmental Impact Assessment – Australian Antarctic Program Aviation Operations 2020-2025 to minimise impacts to wildlife from aircraft noise disturbance and visual stimuli. Noise and wildlife monitoring are requirements of the AAD’s Aviation Operations Environmental Monitoring Plan. Monitoring of noise is relevant to all aircraft activities undertaken by the Australian Antarctic Program (AAP), including rotary and fixed-wing aircraft, remotely piloted aircraft, intra- and inter- continental flights, and airdrops.The monitoring conducted under the Aviation Noise and Wildlife Monitoring Program incorporates both visual and acoustic impacts to wildlife while AAP aircraft are in operation. The Program has been designed primarily to ascertain the noise from aircraft at a range of distances, and to detect any acute responses to aircraft. These generally manifest as immediate behavioural changes that are readily observable via footage or direct observation. A ‘Before-During-After’ (BDA) approach is used to provide a Control/Impact design to the monitoring program, with the Before temporal phase being the control phase of the monitoring event (i.e., before an aircraft event such as a pass-by, take-off or landing) and the During-After phases being the impact phases. In the 2021-22 season, sound meters and video cameras were set up close to (but not within 20 m of) wildlife near to Davis station, East Antarctica, to monitor aircraft sound received at the wildlife’s location, and any behavioural changes. There were 3 monitoring locations in the 2021-22 season:•    Davis Beach: -68.577483°, 77.965983° (precise location of equipment varied depending on the location of wildlife along the beach)•    Marchants Landing: -68.581090°, 77.956380°•    Black Bluff: -68.572633°, 77.967950°All aircraft noise recordings were of single-engine AS350 B3 “Squirrel” helicopters.The following data streams were captured for each monitoring event:•    Flight data (aircraft type, coarse airframe tracking data)•    Behavioural data (video recordings of wildlife response)•    Sound data (audio recordings of ambient and aircraft sounds), and •    Field data (monitoring event data and meteorological data to provide context to the results).Datasets and documents:This dataset contains the raw sound level data collected for the AAD’s Aviation Noise and Wildlife Monitoring Program 2021-22. During each monitoring event, sounds were recorded continuously by a calibrated Rion NL-52 EX sound meter. Calibrations were validated before and after the field measurements using a calibrated source with a 1 kHz tone at a level of 94 dB re 20 μPa.The acoustic recordings were separated into four time periods: Before, During, and After periods, which were based on the timing of each aviation event, and Ambient periods, which captured sound levels during monitoring events when no aviation activities occurred (this occurred on 2 occasions when aviation activities were cancelled following equipment set-up). Ambient sound was defined as the all-encompassing sounds at a point, comprising sound from all sources near and far. This included anthropogenic sounds from station activities that were not related to aviation operations. Time periods were defined as follows:•    Before periods commenced once voice notes and set-up sounds were no longer able to be heard on the recording and ended 1 minute before the start of the During phase. •    During periods captured periods when aircraft sounds could be heard on the recording, with the start and end times delineated when the LAeq was approximately 5 dB above ambient sound levels. •    After periods commenced 1 minute after the end of a During phase and ended either 1 minute prior to the next During phase, after a maximum of 1 hour, or immediately prior to the first detection of sounds related to equipment pick-up (i.e. the end of the monitoring event). •    Ambient periods commenced once equipment set-up sounds were no longer able to be heard on the recording and ended immediately prior to the first detection of equipment pick-up sounds.Sound playbacks and time traces of the audio recordings were reviewed to assist with confirming the start and end times of each time period.

澳大利亚南极分部（Australian Antarctic Division，AAD）的航空噪声与野生动物监测项目（下称"本项目"）于2021年启动，旨在评估《2020-2025年澳大利亚南极计划航空作业环境影响评估》中提出的减缓措施的有效性，以降低航空器噪声干扰与视觉刺激对野生动物的影响。航空噪声与野生动物监测是AAD航空作业环境监测计划的法定要求。

噪声监测适用于澳大利亚南极计划（Australian Antarctic Program，AAP）开展的所有航空作业，包括旋翼机、固定翼飞机、遥控航空器、洲际内部与跨洲际航班以及空投作业。

本项目开展的监测内容涵盖AAP航空器运行期间对野生动物产生的视觉与声学影响。项目核心目标为测定不同距离下航空器的噪声水平，并探测野生动物对航空器的急性应激反应——此类反应通常表现为可通过影像或直接观测到的即时行为变化。

本项目采用"前-中-后（Before-During-After，BDA）"研究框架，构建对照/影响实验设计：其中"前"阶段为监测事件的对照期（即航空器飞越、起飞或着陆等事件发生前），"中"与"后"阶段为影响期。

在2021-2022年度科考季，研究人员于南极东部戴维斯站附近（但与野生动物的距离不低于20米）布设了噪声计与摄像机，以监测野生动物栖息位置的航空器噪声，并记录其行为变化。该季度共设置3个监测点位：
• 戴维斯海滩（Davis Beach）：坐标-68.577483°，77.965983°（设备精确位置将根据沿岸野生动物的分布进行调整）
• 马钱茨登陆点（Marchants Landing）：坐标-68.581090°，77.956380°
• 布莱克布拉夫（Black Bluff）：坐标-68.572633°，77.967950°

所有采集的航空器噪声数据均来自单引擎AS350 B3"松鼠"直升机。

每个监测事件均采集以下四类数据流：
• 飞行数据：航空器类型、粗粒度机身追踪数据
• 行为数据：野生动物反应的视频记录
• 声学数据：环境与航空器噪声的音频录制
• 野外数据：监测事件记录与气象数据，用于为结果分析提供背景支撑

### 数据集与相关文档
本数据集包含澳大利亚南极分部2021-2022年度航空噪声与野生动物监测项目采集的原始声级数据。在每个监测事件中，经校准的Rion NL-52 EX型声级计将持续记录噪声数据。野外测量工作开展前后，均使用输出94 dB re 20 μPa的1 kHz音调校准源对声级计进行校准验证。

声学录音被划分为四个时间段：前（Before）、中（During）、后（After）阶段（基于单次航空事件的时间节点），以及环境（Ambient）阶段（用于捕获无航空作业期间监测点的声级数据——该情况共出现2次，即设备布设完成后航空作业取消的时段）。环境声指监测点处的全范围声源，涵盖远近各类声源，其中也包含站区非航空作业的人为活动噪声。各时间段的定义如下：
• 前阶段：当录音中无法再采集到语音记录与设备布设的声响时开始，至中阶段开始前1分钟结束。
• 中阶段：录制到航空器噪声的时段，其起止时间以等效连续声级（LAeq）约高于环境声级5 dB为界定标准。
• 后阶段：从中阶段结束后1分钟开始，至下一个中阶段开始前1分钟结束（最长持续时长不超过1小时），或直至首次检测到设备回收相关声响（即监测事件结束）前即刻终止。
• 环境阶段：当录音中无法再采集到设备布设声响时开始，至首次检测到设备回收声响前即刻结束。

研究人员通过音频回放与绘制音频时程曲线，辅助确认各时间段的起止节点。