Estimating offshore oil production using DMSP-OLS annual composites

Abstract

Offshore oil exploitation is expanding worldwide in response to the increasing demand for global energy. The long-term acquisition of information on offshore oil production is essential to solve geo-political conflicts and to control marine pollution. However, such information is either dispersed among different authorities or may not even exist. Night-Time Lights (NTL) data has advantages in terms of synoptic coverage and repeatability, providing the opportunity to collect information about marine resources and energy. Until recently, estimating offshore oil production using NTL data was still challenging, largely due to the inability of distinguishing the NTL of oil and gas production. Here, we present an approach for retrieving the spatio-temporal distribution of offshore oil production using DMSP-OLS annual composites. Starting with the geo-locations of offshore platforms, we first propose a Method for Platform Type Classification (MPTC) to discriminate oil platforms from gas platforms. A Model for Oil Production Estimation and Assignment (MOPEA) was then designed by correlating the sum of brightness from oil platforms with offshore oil production. Given worldwide data availability, the offshore regions of the United Kingdom (UK) were used as the initial study area. The principal results are as follows: (i) the overall accuracy of the MPTC and the relative error of the MOPEA were 87.8% and 11.5%, respectively, and the production of each oilfield was in order of magnitude agreement with reality; (ii) there were 365 oil platforms and 258 gas platforms in the UK during 1992–2013, with a distinct spatial distribution north and south of the latitude of 55°N; and (iii) the offshore oil production of the UK declined substantially during 1992–2013, from 9.92 × 107 to 5.63 × 107 sm3, despite an increase in the number of oilfields from 39 to 120 plots; this was mainly because the loss of production in previously highly productive oilfields was too great to be offset by the increased number of low production oilfields. The regional transferability of the MPTC and MOPEA was then validated with reference to three other offshore regions (the Gulf of Guinea of Nigeria, the South China Sea, and the northern Gulf of Mexico of the USA) with satisfactory results. In addition, the MPTC and MOPEA are demonstrated to be capable of extension to the NPP-VIIRS products, paving the way for future applications.