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Introduction
Published in Masanobu Shimada, Imaging from Spaceborne and Airborne SARs, Calibration, and Applications, 2018
Global warming is one of the serious issues that humans face, and they should take action for their future survival. Global warming occurs due to interactions between humans and nature and has accelerated since the Industrial Revolution of the late 18th century. During the last several decades, thematic understanding of the Earth's environment has increased our knowledge about nature's diversity, warning us about the impact of man's actions on our way of life. Since the early 1970s (and particularly with the development of the Landsat program in 1972), the use of remote sensing technologies based on space- and aircraft has been responsible for much of our understanding about the Earth. The Paris Agreement at the 21st Conference of the Parties to the UN Framework Convention on Climate Change (COP21) implies that the world has decided to take action in fighting the gradual increase of carbon emissions. To this end, remote sensing using spaceborne and/or airborne equipment plays a very important role in observing and measuring the Earth's surface components: forest, ocean, sea-ice, natural disasters, and so on.
Satellite Guided Agriculture: Soil Fertility and Crop Management
Published in K. R. Krishna, Push Button Agriculture, 2017
The satellite aided observation of earth’s natural resources was initiated in 1966 under the name ‘Earth Resources Technology Satellites Program.’ Its name was subsequently changed in 1975. In 1970s, Landsat program managed by NASA highlighted the usefulness of satellites in agriculture and remote sensing of natural resources such as land, soil, water, vegetation, etc. Landsat provided large amounts of data and color pictures of earth. Landsat program was used for several aspects of crop production, such as, mapping soils, topography, cropping systems, forest and vegetation cover, monitoring drought, floods, erosion, locust movement, diseases, etc. Landsat was extensively used in compiling weather data for agriculturists and to note effects of global climate change. Reports suggest that first Multi-Spectral Scanners (MSS) was devised and tested in 1969. The era of satellite imagery began with first use of MSS to observe half domes of Yosemite National Park.
Land Degradation Assessment and Monitoring of Drylands
Published in Prasad S. Thenkabail, Remote Sensing Handbook, 2015
Marion Stellmes, Ruth Sonnenschein, Achim Röder, Thomas Udelhoven, Stefan Sommer, Joachim Hill
The Landsat program consists of a series of multispectral optical sensors that record the reflected radiance in the visible to middle infrared domain (complemented by band[s] in the thermal domain) that allows the derivation of several surrogates related to vegetation properties (Fang et al., 2005). Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+), and Operational Land Imager and Thermal Infrared Sensors (OLI/TIRS), respectively, are providing data of the earth’s surface with a spatial resolution of 30 m × 30 m since 1982 (Goward and Masek, 2001). The temporal revisit rate of the sensor is 16 days and could theoretically provide a time series of earth observations with similar density compared to those provided by coarse-scale sensors, but also in many dryland areas, cloud cover impedes the acquisition of utilizable images. Thus, often only few images of sufficient quality can be acquired per season.
Phenological metrics-based crop classification using HJ-1 CCD images and Landsat 8 imagery
Published in International Journal of Digital Earth, 2018
Xiaochun Zhang, Qinxue Xiong, Liping Di, Junmei Tang, Jin Yang, Huayi Wu, Yan Qin, Rongrui Su, Wei Zhou
The Landsat 8 system is the eighth American Earth observation satellite in the Landsat program. Landsat 8 OLI has a spatial resolution of 30 m for multi-spectral bands and 15 m for the panchromatic band 8, with a revisit time of 16 days. In our study, the Landsat 8 OLI image (path 123 and row 39) from 31 July 2013 was selected for masking non-vegetation areas using its pan-sharpened multi-spectral bands, as it has similar spectral characteristics with the HJ-1 CCD (CCFRSDA 2014a; USGS 2015). The specific comparisons between Landsat 8 OLI imagery and HJ-1 CCD are listed in Table 2. We used the panchromatic band 8 at 15 m resolution, and increased the spatial resolution of the multi-spectral bands (bands 1–7) from 30 m to 15 m by applying the pan-sharpening technique (Johnson, Scheyvens, and Shivakoti 2014). Although the 16-day temporal resolution limits the retrieval of crop biophysical parameters that are rapidly changing during the season, 15 m pan-sharpened Landsat 8 image is more appropriate for smaller non-vegetation surface features for comparisons with 30 m HJ-1 CCD images. Therefore, the Landsat 8 image in July was used for discriminating vegetation areas from non-vegetation areas.
A rule-based semi-automatic method to map burned areas in Mediterranean using Landsat images – revisited and improved
Published in International Journal of Digital Earth, 2021
Nikos Koutsias, Magdalini Pleniou
The Landsat series has a long history of data capture, starting with the launch of Landsat 1 on 23/07/1972 with the Multi-Spectral Scanner (MSS) on board (originally known as Earth Resources Technology Satellite [ERTS]). Since that time, Landsat satellites have been taking repetitive images of the Earth’s surface at the continental scale, thus creating a huge historical archive that can be used to reconstruct the past (Nioti, Dimopoulos, and Koutsias 2011). Landsat 1, 2 and 3 carried the Multi-Spectral Scanner (MSS), whereas Landsat 4 and 5 carried the on-board Thematic Mapper (TM), an advanced multispectral scanning radiometer that had higher spatial and spectral resolution than Landsat 1–3 and an improved geometric accuracy. Following the failure of Landsat 6, Landsat 7 was successfully launched on 15 April 1999, carrying the Enhanced Thematic Mapper Plus (ETM+). ETM+ data offer seven bands as TM which cover the visible, near, shortwave and thermal infrared part of the electromagnetic spectrum and additionally a high-resolution panchromatic band (for the first time in the Landsat series). The spatial resolution ranges from 15 to 60 m. Landsat 8 (OLI- Operational Land Imager and TIRS – Thermal Infrared Sensor) was launched on 11 February 2013, and had three new bands along with two additional thermal bands. Specifically, two spectral bands correspond to (i) a deep blue visible channel (band 1) specifically designed for water resources and coastal zone investigation, and (ii) a new infrared channel (band 9) for the detection of cirrus clouds (Koutsias and Pleniou 2015). Landsat 9, expected to be launched in March 2021, is a partnership between the National Aeronautics and Space Administration (NASA) and the U.S. Geological Survey (USGS) that will continue the Landsat program. Landsat 9 will carry the Operational Land Imager 2 (OLI–2), and the Thermal Infrared Sensor 2 (TIRS–2) that is a copy of Landsat 8’s OLI. Landsat 9 will replace the current orbit of Landsat 7, and will image the Earth every 16 days in an 8-day offset with Landsat 8. A diagram showing comparatively the spectral bands of the Landsat series is provided in Figure 1.