COCONet and TLALOCNet: Providing the Intra-Americas Seas Region with Enhanced Atmospheric Observational Capacity

The Intra-Americas Sea (IAS) experiences strong seasonal to interannual variability related to the seasonal migration of the intertropical convergence zone (ITCZ) and large-scale tropical modes including the El Nino Southern Oscillation, the Madden-Julian oscillation and the Atlantic meridional mode.  On more regional scales, IAS weather is strongly modulated by low-level wind jets, the mid-summer drought (MSD), tropical easterly waves, tropical cyclones and the diurnal cycle, which are themselves modulated by the larger scale processes and climatic features. The IAS also influences the weather and climate beyond its boundaries through atmospheric teleconnections and moisture transport.  The current scientific understanding of the modes of variability in the IAS and their potential for improving predictability on subseasonal and longer time scales, as well as secular projections, is inadequate.  The ability to address both the important scientific questions of the region, as well as provide resources for water resource management and disaster preparedness hinges significantly on the modernization of observational networks within the region.  The Continuously Operating Caribbean GPS Network (COCONet), funded by the National Science Foundation (NSF), is a low-cost suite of measurements that begins to address these needs.  The COCONet data archive consists of 145 continuous Global Navigation Satellite System (cGNSS) and meteorology stations across the Caribbean and Central America.  COCONet provides surface observations of wind speed and direction, barometric pressure, air temperature, humidity and precipitation.  The GNSS signal also provides continuous all weather, high frequency (5-30 minute) total column precipitable water vapor.  A similar network, the Trans-boundary, Land and Atmosphere Long-term Observational and Collaborative Network (TLALOCNet), also funded by NSF, is now operational with 37 GPS-Met stations across much of Mexico. Together these cGNSS networks provide critical observational infrastructure to a region that is impacted seasonally and interannually with large fluxes of atmospheric moisture from the Pacific, the Gulf of Mexico and the Caribbean.  These networks also serve as a backbone for short-term process studies aimed at better understanding the mesoscale convective activity across the region.  Here we present a summary of the instrumentation and some results based on these data sets.