Texts types, also known as genres, refer to categories with different purposes. Read the text thoroughly to mark the option which describes the communicative purpose desired.


Could Climate Change Cause More Lakes to Turn Bright Pink?


Ponds with bubblegum-pink water may sound like something straight out of a dream or a fairytale, but some experts say climate change might actually lead to pinker waters across the world. In Hawaii, U.S. Fish and Wildlife Service staff at Keālia Pond National Wildlife Refuge have been monitoring unusually pink water in the park since October 30. Initially, it was feared the color was a sign of a toxic algal bloom, such as the type that produces red tides, but preliminary analysis suggested the culprits were single-celled, salt-loving halobacteria. These bacteria are responsible for turning other bodies of water pink, including the Great Salt Lake’s North Arm in Utah. This area of the lake was separated from the South Arm in the 1950s with the construction of a railroad causeway, this cut off the North Arm from any influx of freshwater, raising its salinity to an average of 26 to 30 percent – double that of the South Arm – and making it an attractive environment for pinkish-orange algae (Dunaliella salina) and violet-pinkish bacteria (Halobacterium and Halococcus).
Other naturally occurring pink lakes are spread out across the world. Lake Retba in Senegal, Salinas de Torrevieja in Spain and several lakes in the south of Western Australia have all taken on a rosy hue from their resident bacteria. While the lakes may look striking, any increase in Barbie Dreamhouse-colored waters may be a sign of warming temperatures and drier conditions driven by climate change.
Keālia Pond’s unusual pink water certainly seems connected to drought. As of December 19, much of Maui is under abnormally dry to severe drought conditions. Normally, the Waikapu Stream flows into the pond, raising water levels and reducing salinity. But that hasn’t happened for a long time, so the salinity of the Keālia Pond outlet is currently greater than 70 parts per thousand – twice that of seawater.


(Available in: https://www.smithsonianmag.com.)