Atmospheric State - Upper Air State

Measurements of various upper atmosphere conditions.

Specific Measurements:

Advective tendency: The large-scale advective tendency of temperature and moisture used to force SCMs and CSRMs, derived from constrained variational analysis.

Atmospheric moisture: The moisture content of the air as indicated by several measurements including relative humidity, specific humidity, dewpoint, vapor pressure, water vapor mixing ratio, and water vapor density; note that precipitable water is a separate type.

Atmospheric pressure: The pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above the point in question.

Atmospheric temperature: The temperature indicated by a thermometer exposed to the air in a place sheltered from direct solar radiation.

Atmospheric turbulence: High frequency velocity fluctuations that lead to turbulent transport of momentum, heat, mositure, and passive scalars, and often expressed in terms of variances and covariances.

Convection: Vertical motion within the atmosphere due to thermal instability, with important impacts on the type cloud systems that can develop.

Horizontal wind: The horizontal wind in terms of either speed and direction, or the zonal (u) and meridional (v) components.

Ice water content: The concentration (mass/vol) of ice water particles in a cloud.

Lightning stroke: Lightning stroke location, type, and intensity

Liquid water content: The concentration (mass/vol) of liquid water droplets in a cloud.

Liquid water path: A measure of the weight of the liquid water droplets in the atmosphere above a unit surface area on the earth, given in units of kg m-2.

Planetary boundary layer height: Top of the planetary boundary layer; also known as depth or height of the mixing layer.

Precipitable water: Total amount of water vapor in a vertical column of air, often expressed as the depth of the layer of water that would be formed if all the water vapor were condensed to liquid water.

Radiative heating rate: The heating rate due to the divergence of long and shortwave radiative flux.

Vertical velocity: The component of the velocity vector, along the local vertical.

Virtual temperature: The virtual temperature Tv = T(1 + rv/ε), where rv is the mixing ratio, and ε is the ratio of the gas constants of air and water vapor (0.622).


Radiometric terms for the IASOA data vocabulary are taken from the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) program’s measurement vocabulary. For the full reference, please visit: