The Earth-Observing Aqua Satellite Mission: 20 Years and Counting.

The Earth-observing Aqua spacecraft was launched on 4 May 2002 and has now completed 20 years of collecting and transmitting data regarding the Earth's radiation budget, atmosphere, oceans, land, and ice. Although launched with a design life of 6 years, four of its instruments continue to operate and provide high-quality data streams more than 20 years after launch. The Aqua data are readily available to users worldwide and have been used in thousands of scientific publications and in numerous practical applications, including weather forecasting, air-quality assessments, and monitoring of forest fires, dust storms, volcanic ash plumes, oil spills, and crop yields.

A 40-y record reveals gradual Antarctic sea ice increases followed by decreases at rates far exceeding the rates seen in the Arctic.

Following over 3 decades of gradual but uneven increases in sea ice coverage, the yearly average Antarctic sea ice extents reached a record high of 12.8 × 10 km in 2014, followed by a decline so precipitous that they reached their lowest value in the 40-y 1979-2018 satellite multichannel passive-microwave record, 10.7 × 10 km, in 2017.

Spatially mapped reductions in the length of the Arctic sea ice season.

Unlabelled: Satellite data are used to determine the number of days having sea ice coverage in each year 1979-2013 and to map the trends in these ice-season lengths. Over the majority of the Arctic seasonal sea ice zone, the ice season shortened at an average rate of at least 5 days/decade between 1979 and 2013, and in a small area in the northeastern Barents Sea the rate of shortening reached over 65 days/decade. The only substantial non-coastal area with lengthening sea ice seasons is the Bering Sea, where the ice season lengthened by 5-15 days/decade.

Responding to climate change: Adélie Penguins confront astronomical and ocean boundaries.

Long-distance migration enables many organisms to take advantage of lucrative breeding and feeding opportunities during summer at high latitudes and then to move to lower, more temperate latitudes for the remainder of the year. The latitudinal range of the Adélie Penguin (Pygoscelis adeliae) spans approximately 22 degrees. Penguins from northern colonies may not migrate, but due to the high latitude of Ross Island colonies, these penguins almost certainly undertake the longest migrations for the species.