The Atmospheric radiation measurement (ARM) program network of microwave radiometers: instrumentation, data, and retrievals

TLDR

The ARM Program operates a network of ground‑based microwave radiometers at the Climate Research Facility. This paper presents an overview of ARM’s microwave instrumentation, calibration, data, and retrievals, and describes the network’s design for higher‑accuracy PWV and LWP retrievals with well‑characterized uncertainties. The network now includes 22 radiometers covering 22–197 GHz, consistently calibrated, with a new generation of three‑channel units being deployed at all ARM sites. Data and retrievals from the network have been available for nearly 20 years, providing high‑quality, continuous datasets for diverse scientific applications. Abstract.

Abstract

Abstract. The Climate Research Facility of the US Department of Energy's Atmospheric Radiation Measurement (ARM) Program operates a network of ground-based microwave radiometers. Data and retrievals from these instruments have been available to the scientific community for almost 20 yr. In the past five years the network has expanded to include a total of 22 microwave radiometers deployed in various locations around the world. The new instruments cover a frequency range between 22 and 197 GHz and are consistently and automatically calibrated. The latest addition to the network is a new generation of three-channel radiometers, currently in the early stage of deployment at all ARM sites. The network has been specifically designed to achieve increased accuracy in the retrieval of precipitable water vapor (PWV) and cloud liquid water path (LWP) with the long-term goal of providing the scientific community with reliable, calibrated radiometric data and retrievals of important geophysical quantities with well-characterized uncertainties. The radiometers provide high-quality, continuous datasets that can be utilized in a wealth of applications and scientific studies. This paper presents an overview of the microwave instrumentation, calibration procedures, data, and retrievals that are available for download from the ARM data archive.