Part 1—Download Software and Data
Step 1 Download and Install ImageJ SoftwareImageJ is in the public domain. It can be freely downloaded and installed on any computer including those at schools, homes, and businesses.
- Go to the ImageJ Download page and open it in a new window.
- Click the link that appears directly below the name of your computer's operating system (e.g., Mac, Linux, Windows). This action will transfer a compressed file of the software to your computer. Your browser should automatically expand the file, creating an ImageJ folder on your computer's hard drive.
For more detailed instructions from the ImageJ website, click Installation Instructions, then select your operating system.
Step 2 Update or Downgrade ImageJ
Double-click the ImageJ icon to launch the application and choose Help > Update > ImageJ.... A window will appear, telling you the version you are currently running and a list of upgrade versions. Choose the version you want to upgrade to (usually the most recent, or default version) and click OK. After the update downloads, you will need to re-launch ImageJ to run the new version.
ImageJ is a professional research and analysis tool, and is under constant development. If the latest update of the application introduces new bugs or errors, or has an unfamiliar interface that does not match the written instructions, and screen shots provided, you can downgrade your copy of ImageJ to an older, more stable or familiar version. The version used in this chapter is 1.45.
Step 3 Locate and Download Ozone Images
Go to the TOMS file transfer protocol site to locate and download the TOMS EarthProbe images for October 1st, 1996-2005.
- Click this link to go through the site's FTP (File Transfer Protocol) interface. This link takes you to three folders: global, npole, and spole. Choose "spole" for the Antarctic (South Pole) images.
- Once in the "spole" folder, you will need to open the correct "Year" folder. In this case, the 1996 folder is shown.
- Once in the "Year" folder, scroll down, and choose the date that interests you. October 1996 is shown as .../IM_ozspl_ept_19961001.tif
- Once you have located the correct image, right-click (or ctrl-click on Macs) and choose File > Save Link As......
- Save the image in a new folder named "TOMS Images" on your desktop, or documents folder. Keep the default name for the image, or give it a name that includes the date it represents.
- Right-click the image (Mac users-hold down the ctrl key and click) to display a menu of choices. Select File > Save Link As....., Save As Source... or a similar command.
- When prompted for a location to store the image, make a new folder named TOMS Images.
- Keep the default image name (it tells the date), and click Save.
- After you've downloaded the first image, click your browser's back button. Select the next folder, 1997, scroll down and locate the next image, then save it to your folder of images.
- Repeat these steps until you've requested and saved TOMS images of October 1 for every year from 1996 through 2005. You will have 10 images.
- Download a compressed file that contains the TIFF images:
Right-click (ctrl-click on Macs) this link to download a zipped file of the TIFF images ( 369kB Jan30 07). Choose the "Download Link to Disk" or "Save Link As..." option. Once the file downloads, you may need to double-click it to decompress it. The decompressed file will be a folder named Ozone TIFFs. Open the images from within the ImageJ application as directed in Step 1 of Part 2.
- Alternately, if you're not successful with the link above, try this compressed file ( 538kB Apr4 06) instead.
NOTE: If saving or downloading the image is not an available option on your computer, see the Troubleshooting Tips below.
Some browsers have been set to display TIFF images within Quicktime Player, and Save Image as... is not an option. Choose Save Source As... from within Quicktime Player. If you can change the preferences of your browser to display TIFF images directly in the browser window, this may allow you to save them.
While our goal is for you to be able to download and analyze whichever ozone images you want directly from the TOMS ftp site, we're offering a link to a compressed folder of the necessary images so you can work through the analysis presented in this activity.