The Defense Meteorological Program (DMSP) Operational Line-Scan System (OLS) has a unique capability to detect visible and near-infrared (VNIR) emission sources at night. Version 4 of the DMSP-OLS Nighttime Lights Time Series consists of cloud-free composites made using all the available archived DMSP-OLS smooth resolution data for calendar years. In cases where two satellites were collecting data, two composites were produced. Image and data processing by NOAA's National Geophysical Data Center. DMSP data collected by US Air Force Weather Agency.

The Defense Meteorological Program (DMSP) Operational Line-Scan System (OLS) has a unique capability to detect visible and near-infrared (VNIR) emission sources at night. This collection contains global nighttime lights images with no sensor saturation. The sensor is typically operated at a high-gain setting to enable the detection of moonlit clouds. However, with six bit quantization and limited dynamic range, the recorded data are saturated in the bright cores of urban centers. A limited set of observations at low lunar illumination were obtained where the gain of the detector was set significantly lower than its typical operational setting (sometimes by a factor of 100). Sparse data acquired at low-gain settings were combined with the operational data acquired at high-gain settings to produce the set of global nighttime lights images with no sensor saturation. Data from different satellites were merged and blended into the final product in order to gain maximum coverage. For more information, see this readme file from the provider. Image and data processing by NOAA's National Geophysical Data Center. DMSP data collected by US Air Force Weather Agency.

The dataset contains (1) temporally calibrated DMSP-OLS NTL time series data from 1992-2013; and (2) converted NTL time series from the VIIRS data (2014-2024)Spatial resolution: 30 arc-seconds (~1km)Information about the composited images from the calibrated DMSP dataset:F10(1992-1994); F12(1995-1996); F14(1997-2003); F16(2004-2009); F18(2010-2013)We suggested using pixels with DN values greater than 7.

Cloud-free coverages (cf_cvg) tally the total number of observations that went into each 30 arc second grid cell. This image can be used to identify areas with low numbers of observations where the quality is reduced. In some years there are areas with zero cloud-free observations in certain locations. This composite set is a component of the DMSP-OLS nighttime lights imagery for the years 1992-2013. The individual images are cloud-free composites made using all the available archived DMSP-OLS (Defense Meteorological Satellite Program - Operational Linescan System) smooth resolution data for calendar years. In cases where two satellites were collecting data - two composites were produced. The products are 30 arc second grids, spanning -180 to 180 degrees longitude and -65 to 75 degrees latitude. Each composite set is named with the satellite and the year (F121995 is from DMSP satellite number F12 for the year 1995).

国防気象プログラム（DMSP）運用ラインスキャン システム（OLS）には、夜間に可視光と近赤外線（VNIR）の放射源を検出する独自の機能があります。DMSP-OLS 夜間照明時系列のバージョン 4 は、利用可能なすべてのアーカイブ済み DMSP-OLS スムーズ解像度データを使用して作成された、暦年の雲のない複合画像で構成されています。…

국방 기상 프로그램 (DMSP) 운영 라인 스캔 시스템(OLS)은 밤에 가시광선 및 근적외선 (VNIR) 방출 소스를 감지하는 고유한 기능을 갖추고 있습니다. DMSP-OLS 야간 조명 시계열 버전 4는 달력 연도에 사용할 수 있는 모든 보관된 DMSP-OLS 부드러운 해상도 데이터를 사용하여 만든 구름 없는 합성으로 구성됩니다. 두 대의 위성이 데이터를 수집한 경우 두 개의 합성 이미지가 생성되었습니다. NOAA의 National Geophysical Data Center에서 이미지와 데이터를 처리합니다. 미국 공군 기상청에서 수집한 DMSP 데이터입니다.