Technological advancements in MicroElectroMechanical Systems (MEMS) have inspired ENSCO, Inc. to propose a revolutionary observing system called Global Environmental MEMS Sensors (GEMS). The GEMS concept features in situ, micron-scale airborne probes that can measure atmospheric variables over all regions of the Earth with unprecedented spatial and temporal resolution. Meteorological observations from a GEMS network have the potential to provide a quantum leap in our understanding of the Earth’s atmosphere and improve weather forecast accuracy well beyond current capability. In addition to gathering meteorological data, probes could be used for environmental monitoring of particulate emissions, organic and inorganic pollutants, ozone, carbon dioxide, and chemical, biological, or nuclear contaminants. Once the probes settle out of the atmosphere, they could continue making measurements over land or water.

The NASA Institute for Advanced Concepts awarded ENSCO a Phase I grant in May 2001 to validate the viability of GEMS and define the major feasibility issues for the meteorological and MEMS disciplines necessary for system design and development. Our objective is to design an integrated system of probes that measure atmospheric pressure, temperature, humidity and wind velocity (based on changes in probe position) as they are carried by atmospheric currents. Each probe will be self-contained with a power source to provide sensing, navigation, and communication functions. The probes will communicate with each other and remote receiving platforms to form a mobile, in situ network.

Pursuit of the GEMS concept will be guided by realistic projections of progress in the miniaturization of probe components. The ultimate GEMS design will likely require a paradigm shift in the areas of microelectronics and miniaturization to address technical challenges with power, communication, navigation, and networking for micron-scale probes. Organic cells feature complex “machines” and systems that may guide the design and functionality of micro and nanoscale devices and components. Materials science will play a key role to limit probe mass and potentially make them biodegradable, thereby minimizing environmental impacts when the probes settle out of the atmosphere.

Interdisciplinary collaboration is the key element of a design-simulation cycle quantifying trade-offs between weather forecast impacts and sensor characteristics. Probe lifetime may vary significantly depending on factors such as power storage/consumption, sampling rate, communication frequency, and on-board data storage and processing. These characteristics affect the quantity and latency of data available for assimilation into numerical weather prediction models as well as the subsequent forecasts initialized using such data. This paper will examine issues relating to probe deployment/dispersion using the Advanced Regional Prediction System coupled with a Lagrangian particle model and report results of observing system simulation experiments to assess the impact of simulated probe data on forecasts of selected weather events within a regional domain.