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Disaster at Lake Delhi – #Landsat50

Well, it’s Water Wednesday. Today’s Landsat highlight is a time lapse video (2007-2017) showing the effect of a 2010 dam breach on the water level of Lake Delhi located in Delaware County in eastern Iowa. Notice the dramatic decrease in water and the exposure of large sandbars and the refilling of the lake as the dam is restored.


This year we are celebrating 50 years of the Landsat earth observing satellite mission. Landsat data helps us observe changes in our communities and environment over time.


Change Over Time – Flooding on the Landscape (NW Iowa)

Use sliders to compare images.

Today’s image shows an area in northwest Iowa between Spencer (Clay County) and Emmetsburg (Palo Alto County). The two images on the left are showing water levels in 1990 (typical year) and 2022 (recovering from a drought) compared to 1993 (heavy flooding) and 2008 (flooding). Notice the swollen streambanks and flooding along water bodies in the right images.


This year we are celebrating 50 years of the Landsat earth observing satellite mission. Landsat data helps us observe changes in our communities and environment over time.


How are you celebrating the Landsat’s Golden Jubilee?

This image is from the Camp Landsat website: https://landsat.gsfc.nasa.gov/outreach/camp-landsat/

To celebrate the Landsat Golden Jubilee, consider taking a virtual visit to Camp Landsat! This summer Camp Landsat is celebrating this exciting anniversary with 5 weeks of programming, celebrating the 5 decades of Landsat’s continuous mission. This week the theme is People and Places.

Enjoy and explore many activities from Camp Landsat including:

Graphic from GLOBE Program Website: https://observer.globe.gov/do-globe-observer/challenges/land-cover-challenge-2022

Stay Cool and Keep Observing!


Celebrating 50 years of Landsat Earth Observation!

Saturday, July 23, 2022 marked the 50th anniversary of the launch of the USGS/NASA Landsat earth observing satellite mission. With the launch in 1972, Landsat has continued its earth observation mission and become the longest continuous earth observing satellite.

July 1972 – Landsat 1 Launch: This image is from the NASA website: https://www.nasa.gov/directorates/heo/scan/images/history/July1972.html

Enjoy this video recalling the launch and explaining the beginning of the earth observing satellite mission, Landsat 9 – Part 1: Getting off The Ground: https://www.youtube.com/watch?v=FlRf17Egexo.


Keep Observing!


Happy Summer Solstice Week! Let’s head to the lake!

We are continuing our celebration of the 50th year of the US Landsat satellite imagery program. This week we are heading to the lake – Clear Lake, Iowa, located in north central Iowa.

Below are four images showing Summer Solstice (6/13/2019), Fall Equinox (9/17/2019), Winter Solstice (12/22/2019), and Spring Equinox (3/18/2019) from Landsat 8. The images are presented in color infrared which shows vegetation in red rather than green for better contrast.

Observations:

  • At Summer Solstice things are still greening up while at Fall Equinox the fields are all green and some are beginning to be harvested.
  • Observe the different states of the lake: open water, snow covered, and frozen.
  • The topography of the landscape (ie. hills and roughness) are much more apparent with snow on the ground. In the summer/fall images, it all looks flat.

What else do you notice? Happy Observing!


Way back when before the Saylorville Dam – #Throwback Thursday

It’s another Throwback Thursday. Saylorville Lake and Dam are located in Central Iowa northwest of Des Moines, Iowa. The Saylorville complex was built to help with flood control and as a drinking water source for surrounding communities. At normal levels, the Saylorville reservoir stores 21.1 billion gallons of water with capacity at flood levels to hold 204.1 billion gallons of water.

Below are several resources if you are interested to learn more about this important structure north of Des Moines:


This year we are celebrating 50 years of the Landsat earth observing satellite mission. Landsat data helps us observe changes in our communities and environment over time.


Traveling Way Back – Landsat Images From Aprils Gone By

Welcome to another Throwback Thursday. Today we are going back into the archives to compare imagery from the first five Landsat satellites (all images are featured in natural color). Click on each image for a closer view.

  • Try to notice the differences in resolution and image quality between the different years.
  • Another thing to note is the wide seasonal variation between the images. All the images were from the same three week period in April. Some images are have snow while other years are very green.
  • Observe that the Des Moines River is swollen in the Landsat 4 -1983 image.
Landsat 1 – April 5, 1976
Landsat 2 – April 3, 1975

Landsat 3 – April 21, 1980
Landsat 4 – April 15, 1983
Landsat 5 – April 12, 1985

You can explore the raw images using this web app: https://arcg.is/0XrG4f. Happy exploring.


This year we are celebrating 50 years of the Landsat earth observing satellite mission. Landsat data helps us observe changes in our communities and environment over time.


Thanks for stopping by and keep observing the world around you!

Join in the Upcoming Summer GIS Workshop for Educators

Dear Teachers,

As the summer approaches, we wanted to encourage you to save the date for an upcoming GIS workshop for K-12 educators being held at William Penn University in Oskaloosa, Iowa on July 20-21, 2022.  See attached poster for more details.  Also please send us an email if you are interested but can’t make this event.  If there is enough interest, we may hold a second workshop, in August or the fall.

Please contact Amy Logan or Debbie Stevens with any questions.