Post-Hurricane Ivan coastal oblique aerial photographs collected from Crawfordville, Florida, to Petit Bois Island, Mississippi, September 17, 2004

The U.S. Geological Survey (USGS) conducts baseline and storm response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms. On September 17, 2004, the USGS conducted an oblique aerial photographic survey from Crawfordville, Florida, to Petit Bois Island, Mississippi, aboard a Piper Navajo Chieftain aircraft at an altitude of 500 feet (ft) and approximately 1,000 ft offshore (Figure 2, http://pubs.usgs.gov/ds/0945/html/ds945_fig2.html). This mission was flown to collect data for assessing incremental changes since the last survey, flown July 2001 (http://compass.er.usgs.gov/activity_popup.php?id=2561), and can be used for assessing future coastal change. The photographs provided here are Joint Photographic Experts Group (JPEG) images. The photograph locations are an estimate of the position of the aircraft and do not indicate the location of the feature in the images (see Navigation Data page, http://pubs.usgs.gov/ds/0945/html/ds945_nav.html). These photographs document the configuration of the barrier islands and other coastal features at the time of the survey. ExifTool (http://www.sno.phy.queensu.ca/~phil/exiftool/) is a free software program for reading, writing, and manipulating image, audio, and video metadata. ExifTool was used to add the following to the header of each photo: time of collection, Global Positioning System (GPS) latitude, GPS longitude, keywords, credit, artist (photographer), caption, copyright, and contact information. Photographs can be opened directly with any JPEG-compatible image viewer by clicking on a thumbnail on the contact sheet. All image times are recorded in UTC. Table 1 (http://pubs.usgs.gov/ds/0945/html/ds945_table.html) provides detailed information about the assigned location, name, date, and time the photograph was taken along with a link to the photograph. In addition to the photographs, a Google Earth Keyhole Markup Language (KML) file is provided and can be used to view the images by clicking on the marker and then clicking on either the thumbnail or the link above the thumbnail. The KML files were created using the photographic navigation files. Note: A KML number was assigned to each photograph to aid navigation of the Google Earth file. These numbers correspond to the site labels in Google Earth.

美国地质调查局（U.S. Geological Survey, USGS）会开展基线与风暴响应摄影任务，以记录并剖析美国沿海地区应对极端风暴的脆弱性变化。2004年9月17日，USGS搭乘派珀纳瓦乔酋长（Piper Navajo Chieftain）型航空器，从佛罗里达州克劳福德维尔飞往密西西比州小博伊斯岛，在500英尺（ft）高度、距海岸约1000英尺的空域开展了倾斜航空摄影测量（详见图2：http://pubs.usgs.gov/ds/0945/html/ds945_fig2.html）。本次飞行任务旨在评估自2001年7月上一次测绘（http://compass.er.usgs.gov/activity_popup.php?id=2561）以来的渐进式海岸变化，同时可用于未来海岸变迁的评估工作。本次提供的影像均为联合图像专家小组（Joint Photographic Experts Group, JPEG）格式图像。影像拍摄位置仅为航空器当时位置的估算值，无法代表影像中地物的实际位置（详见导航数据页面：http://pubs.usgs.gov/ds/0945/html/ds945_nav.html）。这批影像记录了测绘当日障壁岛及其他海岸地貌的分布形态。ExifTool（http://www.sno.phy.queensu.ca/~phil/exiftool/）是一款可读取、写入与编辑图像、音频及视频元数据的免费软件。本数据集通过ExifTool为每张照片的文件头添加了以下元数据：拍摄时间、全球定位系统（Global Positioning System, GPS）纬度、GPS经度、关键词、署名、作者（摄影师）、说明文字、版权信息及联系方式。用户可通过点击联系表上的缩略图，使用任意支持JPEG格式的图像查看器直接打开照片。所有影像的时间均采用协调世界时（UTC）记录。表1（http://pubs.usgs.gov/ds/0945/html/ds945_table.html）详细提供了照片的指定位置、名称、拍摄日期与时间，以及照片的访问链接。除照片外，本数据集还提供了谷歌地球（Google Earth）的键标记语言（Keyhole Markup Language, KML）文件，用户可通过点击标记，再点击缩略图或缩略图上方的链接，在谷歌地球中查看影像。KML文件基于摄影导航文件生成。注：为便于在谷歌地球文件中导航，每张照片均被分配了专属KML编号，该编号与谷歌地球中的站点标签一一对应。