Ionospheric Parameters such as FoF2, FoF1, FoE derrived from hand scaling of analog Ionograms

Ionograms are recorded tracings of reflected high frequency radio pulses generated by an ionosonde. Unique relationships exist between the sounding frequency and the ionization densities which can reflect it. As the sounder sweeps from lower to higher frequencies, the signal rises above the noise of commercial radio sources and records the return signal reflected from the different layers of the ionosphere.

Ionograms are recorded tracings of reflected high frequency radio pulses generated by an ionosonde. Unique relationships exist between the sounding frequency and the ionization densities which can reflect it. As the sounder sweeps from lower to higher frequencies, the signal rises above the noise of commercial radio sources and records the return signal reflected from the different layers of the ionosphere.

The ionosphere is that part of the Earth's atmosphere that results mainly from the photo ionization of the upper atmosphere. Traditionally, the following ionospheric regions and their approximate height ranges have been designated: D region (60-90 km); E region (90-150 km); F1 region (150-250 km); and F2 region (above 250 km). Ionosondes utilize the radio wave-reflecting properties of the ionosphere. The product of the speed of light in a vacuum and half the elapsed time between vertical transmission of a single frequency electromagnetic wave and reception of the reflected wave at the transmitting location is defined as the virtual height of that frequency. A sweep-frequency ionogram is a plot of virtual height versus frequency and is recorded as instantaneously as possible. These ionospheric data consist mainly of hourly values for at least one of the following characteristics: foF2, M(3000)F2, hF2, foF1, M(3000)F1, hF, foE, hE, foE2, hE2, foEs, fbEs, hEs, fmI, and fxI. The values are five byte (character) fields. The first three bytes of the field are reserved for a numeric value; the last two bytes are reserved for the qualifying and descriptive letter, if present. There are no decimals encoded in these data. Documentation is included. There are two CD-ROM's worth of data. One contains 1957 - 1975 data; the other contains 1976-1990 data. ASCII data files and a DOS-compatible application is included.

Planetary Amplitude index - Bartels 1951. The a-index ranges from 0 to 400 and represents a K-value converted to a linear scale in gammas (nanoTeslas)--a scale that measures equivalent disturbance am- plitude of a station at which K=9 has a lower limit of 400 gammas.

This dataset contains Commercial (Comm) Radio Occultation (RO) Environmental Data Records (EDR) from PlanetiQ. It is from Radio Occultation Data Buy II (RODB-2) Indefinite Delivery/Indefinite Quantity (IDIQ), dated March 27, 2023 to March 26, 2028. For RODB-2 IDIQ, NOAA solicited commercial near-real-time satellite-based Global Navigation Satellite System (GNSS) Radio Occultation (RO) and ionospheric measurements that will be processed into neutral atmosphere and space weather products. These derived products will be fed into NOAA's operational data systems, including weather and space weather analysis and prediction systems, and used for weather, climate, and atmospheric research purposes. CommRO is an is an established method for remote sounding of the atmosphere. The technique uses an instrument in low-Earth orbit to track radio signals from Global Navigation Satellite System (GNSS) transmitters as they rise or set through the atmosphere. The occulting atmosphere refracts or bends the radio signals, and given the precise positions of both satellites, the bending angle can be deduced from the time delay of the signal. Collecting these measurements for a full occultation through the atmosphere provides a vertical profile of bending angles, from which profiles of physical quantities such as temperature, humidity, and ionospheric electron density can be retrieved. These data primarily feed numerical weather prediction (NWP) models that support weather forecasts, and also support space weather analysis/prediction at NOAA.

**Please note, this dataset has been superseded by a newer version (see below). Users should not use this version except in rare cases (e.g., when reproducing previous studies that used this version).** Integrated Global Radiosonde Archive is a digital data set archived at the National Centers for Environmental Information (NCEI). This dataset contains monthly means of geopotential height, temperature, zonal wind, and meridional wind derived from the Integrated Global Radiosonde Archive (IGRA). IGRA consists of radiosonde and pilot balloon observations at over 1500 globally distributed stations, and monthly means are available for the surface and mandatory levels at many of these stations by contacting NCEI Customer Support. The period of record varies from station to station, with many extending from 1947 to 2016. Monthly means are computed separately for the nominal times of 0000 and 1200 UTC, considering data within two hours of each nominal time. A mean is provided, along with the number of values used to calculate it, whenever there are at least 10 values for a particular station, month, nominal time, and level.

**Please note, this dataset has been superseded by a newer version (see below). Users should not use this version except in rare cases (e.g., when reproducing previous studies that used this version).** Integrated Global Radiosonde Archive is a digital data set archived at the former National Climatic Data Center (NCDC), now National Centers for Environmental Information (NCEI). This dataset contains monthly means of geopotential height, temperature, zonal wind, and meridional wind derived from the Integrated Global Radiosonde Archive (IGRA). IGRA consists of radiosonde and pilot balloon observations at over 1500 globally distributed stations, and monthly means are available for the surface and mandatory levels at many of these stations. The period of record varies from station to station, with many extending from 1970 to 2016. Monthly means are computed separately for the nominal times of 0000 and 1200 UTC, considering data within two hours of each nominal time. A mean is provided, along with the number of values used to calculate it, whenever there are at least 10 values for a particular station, month, nominal time, and level.

This dataset contains Commercial (Comm) Radio Occultation (RO) environmental data from UCAR using GeoOptics data, which is an established method for remote sounding of the atmosphere. The technique uses an instrument in low-Earth orbit (LEO) to track radio signals from Global Navigation Satellite System (GNSS) transmitters as they rise or set through the atmosphere. The occulting atmosphere refracts or bends the radio signals, and given the precise positions of both satellites, the bending angle can be deduced from the time delay of the signal. Collecting these measurements for a full occultation through the atmosphere provides a vertical profile of bending angles, from which profiles of physical quantities such as temperature, humidity, and ionospheric electron density can be retrieved. These data primarily feed numerical weather prediction (NWP) models that support weather forecasts, and also support space weather analysis/prediction at NOAA.

The GHCN-Monthly Temperature Version 4 dataset consists of monthly mean temperature (both raw and bias corrected data), monthly mean maximum, and minimum temperature. GHCN-M is the core global land surface air temperature dataset used for climate monitoring and assessment activities. GHCN-M version 4 contains monthly mean temperature for over 25,000 stations across the globe and brings consistency with temperature observations found in the GHCN-Daily dataset.