Category Archives: Remote Sensing

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!


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!

Brushy Creek: The Birth Of A Reservoir – #Time Lapse Tuesday

Today’s time lapse video is highlighting the damming of Brushy Creek and the creation of 690-acre Brushy Creek Lake, Iowa’s deepest artificial lake.

Watch the dam development begin around 1994 and then the lake begin to fill around 1998. The Brushy Creek State Recreation Area is a 6500-acre park located in north central Iowa. To read more about the park at the Iowa Department of the Natural Resources Brushy Creek page: https://www.iowadnr.gov/portals/idnr/uploads/parks/parkmaps/brushycreekmap.pdf


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.


#TimeLapse Tuesday – Spot the Change – Urban Growth of Ankeny, Iowa

What changes do you notice in this Landsat time lapse video?

1) The areas of purple and white in the image are urban areas. Throughout the video they fill in the area from the bottom to the center. The pink areas are farm land.

2) Did you notice the increase in the number of retention ponds (dark blue specks in the urban areas) over time? Retention ponds are used to prevent flooding and provide for water storage in urban areas. As areas become urbanized there is often more surface covered in concrete, parking lots and buildings. There are fewer places for the water to flow directly into the ground.

3) Did you spot the golf course on the northern edge of the city?


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.


This video was created using Google Earth Engine. You can create your own time lapse videos by visiting: https://emaprlab.users.earthengine.app/view/lt-gee-time-series-animator.

#Landsat Throwback Thursday – 50 years of Growth in Dubai

Over the last 50 years, the city of Dubai, in the United Arab Emirates, has transformed from a small fishing and pearl diving village into a luxurious, modern metropolis. The population has grown from just over 100,000 residents in 1972 to an estimated 2.9 million residents in 2022. While the beauty and distinction of this city is undeniable, some question the sustainability of this fast-growing city located in a land of desert and salt water. The images are shown in false color infrared.  Areas appearing red show healthy vegetation. Notice the dramatic change from first image in 1973 (very little vegetation and urbanization) to 2022 with many areas of red far from the water. 

To create these images, individual bands were downloaded from the United States Geological Survey’s Earth Explorer Website (https://earthexplorer.usgs.gov/) in April 2022. The composite false color infrared images were created in ArcGIS Pro using the composite imagery processing tool.


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.


Greetings from Camp Landsat: Cities and Suburbs

Greetings from Camp Landsat!

Postcards From Camp: Cities & Suburbs
Are you exploring any cities this summer? Rain or shine, urban planners use Landsat to take stock of city growth and its environmental impact. The front of this postcard features a natural-color Landsat 8 image of Ocean Flower Island in Hainan, China acquired May 6, 2020.

This week’s camp theme is Cities and Suburbs and focuses on the growth of cities and urban areas as seen over time through Landsat images. Urban growth has impacts on the surrounding environment. Visit Camp Landsat to learn more and experience a time-laspse video of urban growth in Qatar, a storymap about urbanization of vacation towns, and learn about urban heat islands in Minnesota. This week’s camp crafts include Color by Number Image Classification and creating a bird house with a “green roof.” Thank you to our friends at NASA for making this fun summer camp possible!