Nauru: clouds the island makes, pinnacles and soils of Topside, and an endemic reed-warbler

The Atmospheric Radiation Measurement (ARM) programme, run by the U.S. Department of Energy, established its second Tropical Western Pacific site on Nauru. In a 1999 conference paper, Clements and co-authors locate the site at Denigomodu, close to the General Hospital on the island’s west side, 7 m above mean sea level. They describe an opening ceremony on 20 November 1998; ARM’s campaign page dates formal commissioning to 28 November. The site operated with the Nauru Department of Island Development and Industry. ARM’s account of the Nauru Island Effect Study says it ran from November 2001 through May 2003, separating the island’s influence on station measurements. Long and McFarlane later analysed five years of observations. Their abstract estimates that solar heating produces an island effect during about 11% of daylight hours. During the effect, downwelling shortwave radiation is about 17% lower; when clouds are also present, the frequency of cloud bases at 500–1,000 m is 15–20% higher. Averaged over daylight, low-cloud occurrence is about 2% higher and radiation about 2% lower; over 24 hours, each difference is about 1%. ARM dates the station’s shutdown to 30 August 2013.[1][2][5][3][4]

Buden’s 2008 survey describes Nauru as a raised atoll of 21 km². A narrow coastal belt rises over a steep scarp to the central plateau, which Morrison and Manner note is known locally as Topside. Their 2005 study reconstructs four broad soil associations across the reef-fringed coast, the plateau and scarp, and the low terrain around Buada. In their account, small remnants of three original associations remain; relatively deep soil profiles without substantial pinnacle influence have disappeared completely. Buden describes coral-limestone pinnacles 4–8 m high and notes a small settlement beside brackish Buada Lagoon in the island’s southwest.[7][6]

Donald Buden’s 2008 paper reviews 25 indigenous bird species. The abstract marks seven as confirmed or probable resident breeders; the discussion also includes former breeders in that group. Buden names two indigenous breeding land birds: the pigeon Ducula oceanica and Nauru’s endemic reed-warbler, Acrocephalus rehsei. After a six-hour stop on 24 July 1880, Otto Finsch noted the reed-warbler; his 1883 account described it as a new species. Based on his 2006–07 visits, Buden estimated about 5,000 reed-warblers on the island. He observed them in remnant plateau forest, gardens and regenerating scrub in mined areas. His field account also documents noddy-catching around the plateau interior. Buden reports fewer black noddies than formerly, noting continuing hunting and mining-related habitat loss.[7]