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Solar Spectral Measurements
Published in Frank Vignola, Joseph Michalsky, Thomas Stoffel, Solar and Infrared Radiation Measurements, 2019
Frank Vignola, Joseph Michalsky, Thomas Stoffel
The National Weather Service launches radiosondes on balloons twice each day as part of a worldwide network of measurements that profile temperature, humidity, pressure, and wind speed and direction. The launches are coordinated with launch times centered on 0 and 12 GMT. The website http://www.wmo.int/pages/prog/www/ois/volume-a/vola-home.htm contains a list of stations launching radiosondes throughout the world. Although relative humidity is measured on these radiosondes, dew point temperature is the reported value. The actual vapor pressure e for any measurement in the profile can be calculated from the dew point temperature Td using () e=6.1121⋅exp(17.502⋅Td240.97+Td)
Blockchain versus IOTA Tangle for Internet of Things
Published in Sonali Vyas, Vinod Kumar Shukla, Shaurya Gupta, Ajay Prasad, Blockchain Technology, 2022
C. P. Igiri, Deepshikha Bhargava, C. Udanor, A. R. Sowah
Kevin Ashton first coined the term Internet of Things in 1999 during his proposal of integrating RFID into Procter and Gamble's supply chain (Ashton, 2009). His idea was that since people are usually very busy, there was a need to use RFID sensors to empower computers to gather information randomly by themselves without being limited by humans entering the data. IoT is seen as the Internet's future, drastically reducing a human-to-human interaction while increasing M2M transactions. It promises to unify everything in our world under one architecture while at the same time giving us control over many things and keeping us informed on the goings-on around us (Bansal and Rana, 2017). IoT as a new revolution of the Internet describes a future with the possibility of connecting all physical devices (Yehia et al., 2015), which will communicate among themselves independently of human intervention. These devices will affect all facets of our everyday life, such as in monitoring our health status, our homes and offices, and water and air quality, among others. The history of IoT can be traced back to the early telemetry system, which began in Chicago around 1912, in which telephone lines were used to monitor data from power plants (Zennaro, 2016). In the 1930s, telemetry expanded to weather monitoring using devices known as radiosondes. The Sputnik, launched by the Soviet Union in 1957 during the space race era, became the basis for aerospace telemetry, which later gave birth to today's global satellite communications. Also, according to Zennaro (2016), M2M technologies began in the 1980s as wired communication began to advance towards wireless in the 1990s. Several enabling technologies that have aided the rise of IoT include ubiquitous connectivity, widespread adoption and expansion of the IP address regime, computing economics, miniaturization, advances in data analytics and the rise of cloud computing.
LIDAR Systems for Atmosphere Monitoring
Published in Ghenadii Korotcenkov, Handbook of Humidity Measurement, 2018
Light detection and ranging (LIDAR) hygrometry is a modern kind of optical methods for control of water vapor in the atmosphere. LIDAR is an optical remote sensing technology that measures properties of scattered light to obtain information about atmospheric composition, clouds, and aerosols (Grant 1991; Turner and Whiteman 2002). It is known that remote control based on absorption measurements can be divided into two main types: passive, for which no special light sources are needed; and active, for measurements that utilize additional sources of electromagnetic radiation. In the first type, the Sun functions as the light source. Light from the Sun is reflected and reemitted from the ground as it passes through a gas plume. As all molecules absorb light in very discrete and narrow wavelength bands of ultraviolet (UV), visible, and infrared (IR) light, by focusing on these bands of absorption, one can observe and predict how much less energy reaches the sensor over a gas plume as opposed to an unaffected area. Using atmosphere modeling software, it is possible to obtain a reasonable value for the concentration of gas. As shown previously, passive methods for studying the atmosphere can be based on using optical, microwave, and terahertz spectroscopy. Using these methods of testing and the methods of processing the information obtained, one can receive information about the temperature and humidity distribution in the height of the atmosphere (e.g., Table 8.1), and on the Earth’s surface, which is essential for the development of models suitable for adequate weather forecasting. As is known, humidity, in particular, is a critical variable in the initialization of these models. Profiles of the water vapor and temperature height distribution can be obtained by using radiosondes. However, it is well known that radiosonde measurements are often not reliable at upper-tropospheric temperatures. Furthermore, the temporal resolution of routine observations performed by weather services is rather low, with typically two radiosonde launches per day. Therefore, important weather phenomena such as the development of the convective boundary layer (CBL) and the passage of cold and warm fronts cannot be resolved. Radiosondes take only one data point per measurement height. Thus, the measured relative humidity (RH) profiles are often not representative. For these reasons, alternatives to routine radiosonde observations are required.
Bivariate Functional Quantile Envelopes With Application to Radiosonde Wind Data
Published in Technometrics, 2021
Weather data obtained from the atmosphere, beginning three meters above the earth’s surface, is known as weather balloon data or upper air data. A small, expendable instrument known as the radiosonde, which is suspended below a 2-m wide balloon filled with hydrogen or helium that ascends through the upper-air, collects and transmits that data back to the ground. The sensors on the radiosonde measure vertical profiles of temperature, humidity, atmospheric pressure, and geopotential height. By tracking the position of the radiosonde in flight, information on wind speed and direction is also obtained. The Integrated Global Radiosonde Archive (IGRA) consists of more than 1500 globally distributed radiosonde observations from different time periods, ranging from the 1960s to the present; an overview of the dataset is given in Durre, Vose, and Wuertz (2006). The National Center for Atmospheric Research (NCAR) Upper Air Database (UADB) contains the longest possible time series of radiosonde data, from the 1920s to the present, at more than 1600 global locations. Analyzing such substantial and complex datasets need a robust analysis. The dataset analyzed in this article is available online for free at https://rda.ucar.edu/datasets/ds370.1/ in the Research Data Archive at NCAR (DSS/CISL/NCAR/UCAR 2014).