Research and Development
For a select list of publications that feature YES scientific instruments, please click here.
Our mission is to develop high quality environmental and laboratory instrumentation to measure weather conditions in all regimes: on the ground, in the air, and on board ships. These measurements cover the spectrum of "mud to sun", that is, from soil moisture, through temperature, humidity, radiation and clouds, all the way up to space weather sensors. Yankee engineers and scientists have worked together with seven different Federal Agencies and hundreds of customers in developing their product line of environmental sensors. Ongoing R&D projects involve these areas:
Dropsonde - NOAA
The US Department Of Commerce (National Oceanic and Atmospheric Administration) has funded YES to develop a low cost dropsonde, suitable for use on Unmanned Aerial Vehicles (UAVs) over data sparse regions. These disposable weather stations are released from a high altitude will measure and telemeter conditions from the release platform down to the water. They will provide NOAA with critical real time data to drive numerical weather prediction models to set their initial conditions. In areas such as the eastern pacific, little data is take and the accuracy of weather forecasts in the western US suffer. Ultimately, NOAA's GUPS concept plans to fly a small network of UAVs to disperse dropsondes across the Pacific Ocean on a periodic basis. Improvements to mesoscale weather model accuracy could provide wide ranging economic and safety benefits to the entire planet.
In 2017, a team of scientists on the NASA Convective Processes Experiment (CPEX) deployed hundreds of Yankee Expendable Digital Dropsonde XDD-938 instruments from NASA's DC-8 aircraft in the North Atlantic Gulf of Mexico and Caribbean Oceanic regions. To learn more visit the Convective Processes Experiment page.
Nighttime Cloud Imager - USAF
The US Department Of Defense (US Air Force ) has funded YES to develop a nighttime version f its Total Sky Imager to support operational requirements of Space Weather operations. By observing clouds in all weather conditions at night, these detectors can automatically determine whether auroral or air glow emissions caused by solar storms or "space weather" are occluded. Solar-induced electromagnetic disturbances are a critical factor in the accuracy of GPS-guided munitions, and often the performance of GPS propagation is questionable. This technology therefore has the potential to save lives of non-combatants in times of conflict. Beyond military applications, another important application area is nighttime airport landing and takeoff safety.
Deployable Micro Weather Station - US Navy
The US Department Of Defense (US Navy) has funded YES to develop a miniature, low cost weather sensor for use in Naval operations. This surface based sensor makes automated pressure, temperature, humidity and wind measurements and automatically telemeters them via low earth orbiting satellite. It can be dropped in ahead of troops or placed semi-permanently for longer deployments. It has important civilian applications involving homeland defense and wildfire weather prediction.
Doppler Lidar - US Navy
The US Department Of Defense (US Navy) has funded YES to develop a Fiber Optic Doppler Lidar for remote sensing of wind speed and direction. Operating in the intrinsically eye-safe and invisible 1.5mm near infrared (NIR) region, its solid state laser diode source and erbium-doped fiber amplifier provides reliable, continuous service at remote locations. Imagine being able to make real time wind profile measurements to hundreds of meters without the expense of installing and maintaining a meteorological tower.
Automated Radiosonde Launcher - NOAA
The US Department of Commerce (National Oceanic and Atmospheric Administration) has funded YES to develop Automated Radiosonde Launcher technology operate in remote locations or when unattended upper air wind/PTU observations are desired. The launcher is a robust system that automates radiosonde observations. Because the ARL automates every step in the launch process it frees personnel to perform more important value-added tasks, and virtually eliminates human errors. At remote sites, it reduces exposure of personnel to hazardous and/or undesirable environmental conditions.
Automated Precipitation Collector - NOAA
The US Department Of Commerce (National Oceanic and Atmospheric Administration) has funded YES to develop a Total Precipitation Collector. It consists of a wet deposition bucket that is normally covered by a motor operated lid during non-precipitation events. The user periodically visits the system to recover its precipitation sample bag for lab analysis. A next-generation, CPU-controlled precipitation sensor controls the open/closed decision. The TPC-3100 Opti-Grid precipitation sensor represents a major improvement over older sampler technology where the earliest light precipitation events were often missed. Often the earliest phases of a precipitation event contain the highest concentrations, and this historical lack of sensitivity has biased sampling.
Wind-Powered Refrigeration - US Dept. of Energy
The National Renewable Energy Lab, a branch of the US Department Of Energy has funded YES to develop an innovative wind-powered refrigeration system. Much like clean drinking water was a major issue two decades ago for villages, reliable refrigeration (or ice) remains a need of most of the third world. The availability of refrigeration is in great demand both in terms of public health and for standard of living reasons. However high electrical energy costs and lack of distribution infrastructure keeps a refrigerator of the reach of most of the world's population.
If ice could be produced for free (or nearly free) for example, many of the world's fishing villages could then successfully transport the fish they harvest to market and convert it to hard currency. An obvious solution is to develop a renewable energy-based system to power refrigeration on a large, "village-wide" scale, much like shared water wells are setup today around the world. Everywhere but in the desert, wind handedly beats solar power in energy-recovered-per-invested-dollar. However, because wind availability generally tends to be erratic in most parts of the world, it is difficult to efficiently couple the needs of a static refrigeration cycle to a wind turbine. YES engineers are developing an adaptive electronic load-matching charge management system that will permit a large-scale commercial ice machine to be directly connected to a >10kW tower-mounted wind turbine.
Improved Solid State UV detection technology
YES is working with a private industry partner to develop and optically test a new breed of band-gap limited solid state UV-B detectors that have the potential to reduce the sensitivity to OOB (visible) light vs. existing SiC and GaP and GaN technologies. We expect to utilize these detectors in future field and space-based UV radiometers.
Image Processing - USDA
Knowledge of cloud cover is an essential meteorological parameter. Clouds play a major role in the energy balance and direction of weather patterns. Until recently, human observers were required to make hourly observations of sky conditions at airports and meteorological stations. The inherent subjectivity of this method produced results that varied widely from observer to observer. In response to this requirement YES introduced the Total Sky Imager, a result of a 1994 USDA Phase II SBIR R&D program. The automated TSI-880 takes digital pictures of the sky, which are analyzed via image processing algorithms to support weather prediction models and forecasting. Current research involves new and improved image processing algorithms for extracting useful data products from present weather images such as winds aloft. The goal is to reduce the dependency on radiosondes for winds and to support the US Federal Aviation Administration's requirement for improved cloud cover and visibility measurements at airports via improved aviation meteorology.
Optical Calibration
Every instrument requires some method of calibration - this is a basic tenet of the field of metrology. Optical calibration of radiometers involves the conversion of the raw analog signal from the detector into engineering units that the user can interpret. In calibrating a radiometer each of the following parameters can influence the output of an instrument:
- angle of incidence from the source (cosine response)
- presence of strong out of bandwidth (OOB) energy
- spectral response
- overall absolute or "voltage sensitivity" response - the detectivity can change over both time and exposure
- local ambient temperature
- mechanical vibration
Thus, in outdoor measurement of atmospheric radiation, accurately characterizing the output that an optical sensor produces in terms of irradiance (W/m2) or spectral irradiance (W/m2-nm) is a particularly difficult challenge. Moreover, moving radiometers from the field to standards labs has the potential to lead to damage or calibration shifts. Optical irradiance calibrations of radiometers in the field, traditionally restricted to indoor optical facilities like at NIST, the PTB or NPL can now be made using our new portable SQM-5002 lamp standard. With its precision power supply and thermally stabilized housing, it represents the state-of-the-art in uniform flux irradiance sources. Initially pioneered by NASA Goddard it was a direct result of a SBIR Phase I R&D program funded by the USDA.
CSU/NREL derives high accuracy column ozone from UVMFR
A team of researchers working at the Natural Resource Ecology Lab have developed and published new algorithms for deriving high accuracy column ozone and aerosol optical depth from UVMFR data. A paper describing the method and results has been submitted for publication. Visit NREL for more information on this important new scientific development.