ences in the system. The system partition may be according to business units rather than regions.
Current surface observation systems in the United States are quite numerous, as discussed in Chapter 2. Many of these networks result from some form of public enterprise, but the private-sector operates numerous networks as well. A well-known high-quality surface meteorological measurement system is the Oklahoma Mesonet (see Box 4.1). This network can be used as an example to denote the system technology (not necessarily the measurement technology) of such networks. The crucial communications component is handled by the Oklahoma Law Enforcement Telecommunication System (OLETS) communications infrastructure. Thus this system has attributes in terms of data bandwidth, space and time scales of observations, and the extent of observations (namely the State of Oklahoma). The Oklahoma Climatological Survey (OCS) receives the observations, verifies the quality of the data, and provides the data to mesonet customers. It only takes 5 to 10 minutes from the time the measurements are acquired until they become available to the public. It should be noted that this observation system consists of a suite of sensors that corresponds to specific technology that can be upgraded to future technologies.
Quality assurance and calibration are important aspects of this system and must be supported by extensive quality control software and a calibration laboratory. Thus this system has underlying technical and architectural aspects (McPherson et al., 2007).
With the Oklahoma Mesonet, the meteorological network and the communication infrastructure are public enterprises. An alternate paradigm was used to develop the Helsinki testbed, a mesoscale observational network in Southern Finland. This network was heterogeneous from inception, and the measurement infrastructure is built around anchor systems such as the Vaisala ultra-high frequency dual-polarization radar. This public-private partnership consists of the Finnish Meteorological Institute, the Vaisala meteorological measurements company, and the University of Helsinki. The testbed provides information on observing systems and strategies, mesoscale weather phenomena, and applications in a coastal high-latitude environment (60-61N, 24-26E). Interest in the Helsinki testbed focuses on meteorological observations and forecasting directed towards meso-gamma scale phenomena that typically last from a few minutes to several hours. These weather events are often too small to be detected by traditional networks. In coastal Finland, such weather events include temperature inversions, sea breeze, fog and low stratus, snow bands, urban heat islands, and convective storms. These and related phenomena such as lightning are often hazardous and cause substantial damage. For instance, fog causes considerable disruption of land, sea, and air traffic. The sea breeze and its phases