Spatiotemporal variability of the gas transfer coefficient (KCO2) in boreal streams: Implications for large scale estimates of CO2evasion

Monthly maps of the ocean—atmosphere CO 2 gas-transfer coefficient are derived from meteorological winds for 1982. The seasonal variations are of the order of a factor 2, mostly in the Northern Hemisphere. A strong meridional pattern is observed: the exchange coefficient is larger at high latitudes than in tropical areas. However, the zonal variations within a latitudinal band (generally a westward enhancement) can be as large as the meridional ones. The representativity of the winds is a major concern: interannual variations of the order of 30 % are documented by an analysis of four years of the monthly transfer coefficient derived from meteorological winds in the Atlantic ocean. In the future, these maps will be obtainable on a routine basis from satellite data. As an example, a map derived for August 1978 from Seasat altimeter winds is compared with the present ones.

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KOEFISIEN TRANSFER GAS (KLa ) PADA PROSES AERASI MENGGUNAKAN TRAY AERATOR BERTINGKAT 5 (LIMA)

Jurnal Dampak ◽

10.25077/dampak.9.2.132-140.2012 ◽

2012 ◽

Vol 9 (2) ◽

pp. 132 ◽

Cited By ~ 1

Author(s):

Suarni Saidi Abuzar

Keyword(s):

Water Quality ◽

Surface Water ◽

Dissolved Oxygen ◽

Transfer Coefficient ◽

Oxygen Concentration ◽

Gas Transfer ◽

Dissolved Oxygen Concentration ◽

Total Height ◽

Water And Wastewater ◽

Gas Transfer Coefficient

ABSTRAKAerasi merupakan salah satu metode yang dapat digunakan untuk menyisihkan kandungan logam dalam air, baik air tanah, air permukaan, maupun air limbah. Salah satu jenis aerator dalam proses aerasi adalah tray aerator. Untuk menganalisis nilai koefisien transfer gas (KLa) pada proses aerasi khususnya tray aerator bertingkat 5 (lima)dengan jarak antar tray 25 cm dan tinggi total 125 cm, perlu dilakukan penelitian dengan tujuan untuk memperoleh nilai KLa. Air dialirkan ke dalam tray aerator bertingkat 5 (lima) dan diukur kandungan Disolved Oxygen (DO) dengan metode water quality checker. Hasil penelitian menunjukan terjadi peningkatan konsentrasi oksigen pada sampel setelah dilakukan aerasi dengan tray aerator bertingkat 5 (lima) dari 5,97 mg/L menjadi 6,34 mg/L dengan nilai koefisien transfer gas (KLa) sebesar 0,045/menit.Kata kunci: Tray Aerator bertingkat 5, Aerasi, Koefisien trasnsfer gas (KLa)ABSTRACTAeration method is one method for removing metalfrom water including groundwater, surface water and wastewater. One of known aerator is method is tray aerator. For analizing gas transfer coefficient (KLa) in aeration method especially in five storey tray aerator with the distance between each aerator was 25 cm and total height was 125 cm. water was discharged in five storey tray aerator and was measured the dissolved oxygen concentration by using water quality checker method. Result showed the increase of oxygen concentration in sample after being aerated in five storey tray aerator, from 5.97 mg/L to 6.34 mg/L with gas transfer coefficient (KLa) 0.045/min. Keywords: Aeration, Five story aerator, Gas transfer coefficient (KLa)

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