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The Indonesian Throughflow (ITF) is a globally important ocean current that fuels heat and buoyancy fluxes throughout the Indo‐Pacific and is known to covary in strength with the El Niño Southern Oscillation at interannual time scales. A climate system with a less well‐quantified impact on the ITF is the East Asian Winter Monsoon (EAWM), which drives less saline surface waters from the South China Sea (SCS) into the Makassar Strait, obstructing surface ITF flow. We present a subannually resolved record of sea surface salinity (SSS) from 1927 to 2011 based on coral δ18O from the Makassar Strait that reveals variability in the relative contributions of different source waters to the surface waters of the Makassar Strait during the boreal winter monsoon. We find that the EAWM (January–March) strongly influences interannual SSS variability during boreal winter over the twentieth century (r = 0.54, p << 0.0001), impacting surface water circulation in the SCS and Indonesian Seas. NRF (Natl Research Foundation, S’pore) Published version

Penelitian dilakukan pada bulan Juni 2004 bertujuan untuk mengetahui keanekaragaman jenis, distribusi dan persen tutupan karang serta faktor-faktor yang mungkin mengancam kerusakan lingkungan hidup di terumbu karang. Metode yang digunakan adalah Line lntercept Transect dan Observasi Langsung di lapangan pada 4 stasiun penelitian.

Penelitian yang dilakukan pada bulan Juni 2004 ini bertujuan untuk mendapatkan data dan informasi ikanikan yang hidup dan berasosiasi dengan karang serta memprediksi faktor-faktor penghambat yang mempengaruhi keberadaan di wilayah perairan pulau-pulau kecil di Kalimantan Barat.Metode yang digunakan adalah sensus visual pada transek garis. Hasil penelitian menunjukkan bahwa jumlah jenis ikan karang berkisar antara 36 sampai dengan 51 jenis dengan kepadatan antara 10 sampai dengan 15 individu per m2. Rata-rata untuk Indeks keanekaragaman jenis (H), Indeks Dominasi (D), Indeks Keseimbangan (E), dan Irian Jaya Reef Diversity Index masing-masing 2,7; 0,1; 0,7; dan 4,5. Persentase ikan kelompok mayor rata-rata 66%, kelompok ikan target 19%, dan kelompok ikan indikator 15%. Sedangkan rata-rata persentase penggolongan ikan berdasarkan pada nilai ekonomi 66% ikan ekonomis rendah, 17% ikan ekonomis sedang, dan 17% ikan ekonomis tinggi. Faktor pembatas distribusi ikan adalah kekeruhan air yang cukup tinggi yang disebabkan oleh sedimen dari daratan. A study conducted in June 2004 aims to obtain data and information of fish living on and associating to coral reefs, and also to assume limitting factors for fish distribution. A sampling method used was visual census on a transect line. The result shows that the number of coral fish ranged from 36 to 51 species. The density of coral fish ranged from 10 to 15 indivdual per m2. The means of Diversity Indeces (H), Dominance Indeces (D), Eveness Indeces, and Irian Jaya Reef Diversity Index indeces were 2.7; 0.1; 0.7; and 4.5, respectively. The percentages of a major fish group, a target fish group, and an indicator fish group were average of 66, 19, and 15%, respectively. The mean percentages of marketable based fish groups consisted of 66% of low valuable fishes, 17% of fair valuable fishes, and 17% of high valuable fishes. The low level of body water transfarancy due to upland sediment was a limitting factor for the attendance of coral fish in the coral reef area of study sites.

We quantify fore-arc deformation using fossil reefs to test the assumption commonly made in seismic cycle models that anelastic deformation of the fore arc is negligible. Elevated coral microatolls, paleoreef flats, and chenier plains show that the Sumatran outer arc island of Nias has experienced a complex pattern of relatively slow long-term uplift and subsidence during the Holocene epoch. This same island rose up to 2.9 m during the Mw 8.7 Sunda megathrust rupture in 2005. The mismatch between the 2005 and Holocene uplift patterns, along with the overall low rates of Holocene deformation, reflects the dominance of elastic strain accumulation and release along this section of the Sunda outer arc high and the relatively subordinate role of upper plate deformation in accommodating long-term plate convergence. The fraction of 2005 uplift that will be retained permanently is generally

Seismic rupture produced spectacular tectonic deformation above a 400-kilometer strip of the Sunda megathrust, offshore northern Sumatra, in March 2005. Measurements from coral microatolls and Global Positioning System stations reveal trench-parallel belts of uplift up to 3 meters high on the outer-arc islands above the rupture and a 1-meter-deep subsidence trough farther from the trench. Surface deformation reflects more than 11 meters of fault slip under the islands and a pronounced lessening of slip trenchward. A saddle in megathrust slip separates the northwestern edge of the 2005 rupture from the great 2004 Sumatra-Andaman rupture. The southeastern edge abuts a predominantly aseismic section of the megathrust near the equator.