NOTE: This WWW page is being phased out. Please go to our NEW ISFS WWW site for the latest information on the Integrated Surface Flux System.

1. ISFF Description

The Integrated Surface Flux Facility (ISFF) is designed to study exchange processes between the atmosphere and Earth's surface. This includes the direct measurement of fluxes of momentum, sensible and latent heat, trace gases, and radiation as well as standard atmospheric and surface variables. With multiple sensors and data systems, measurements of horizontal and vertical gradients also can be made. This facility, formed by integrating [formerly] ATD's former Atmosphere Surface Turbulent Exchange Research facility (ASTER) and Portable Automated Mesonet (PAM III and Flux PAM) facilities, is quite flexible and has been used in Arctic to desert conditions with sensor spacings from 1 m to 60 km (and separations of 1000s of km are possible). Average statistics of all variables, including the second-order moments needed to compute fluxes, are a standard product of ISFF and are available in real-time for display. When possible, every data sample is archived to allow processing using spectral, wavelet, or conditional sampling methods. ISFF also supports the addition of user-supplied sensors with digital or analog outputs at data rates up to 10,000 samples/s. The ISFF is managed by EOL/ISF (formerly ATD/RTF).

ISFF Project Documentation is available online for most projects. For each project listed there is a link to the project report, table of variables, field logbook, data links, and a contact person.

The project reports contain a description of the field site, instrumentation configuration, and data processing steps. For some projects, there are also plots of weather conditions, fluxes, etc.

The field logbook has all information logged by ISF staff and visitors before, during, and after the field campaign. Each entry is indexed by time, location, type (e.g. sensor), and author.

Data available online include 5-minute average statistics (through 4th-order moments for turbulence variables) of all quantities measured. For some projects, "raw" time series of every sample from each sensor also are available. These are processed using the calibrations that are current at the time of download -- users are encouraged to check with SSSF for the status of these calibrations.

3. What's New

ISF regularly upgrades sensors and components of the ISFF facility as new hardware and software capabilities become available and which are appropriate to our mission. Beginning in 2004, a New Data System is being developed that will retain all functionality while expanding computing and processing capacity with reduced power consumption over the previously utilized VME based components. The new system is based upon inexpensive, commercially available PC104 hardware; while operational software has been migrated to run under real-time Linux operating system.

To expand spacial coverage and mobility a new Adaptive Sensor Array approach is being pursued. This concept is based upon the emerging mesh-network techniques being developed at several educational institutions, NCAR and commercial companies. See the Adaptive Sensor Array Power Point Presentation that ISF provided for NSF which outlines this effort and the first deployment of our new data system.

Below is a listing of the most common ISFF sensors. Documentation on all ISFF sensors is available.

Sensor	Manufacturer	Model	Parameter	Rate	#
3-D sonic anemometer	CSI	CSAT3	u,v,w - m/s; Tvs - deg C	60sps	21
UV absorption hygrometer	CSI	KH20	vapor density - gm/m3	20Hz	12
H2O/CO2 Open-path Gas Analyzer	LI-COR	LI-7500	H2O/CO2 concentration	20sps	5
Prop-vane anemometer	NCAR/SSSF - R.M. Young		U, V - m/s	5Hz	7?
Prop-vane anemometer	R.M. Young	9101	U, V - m/s	5Hz	~10
Hygrothermometer	NCAR/SSSF - Vaisala	50Y Humitter	T - deg C; RH -%	1Hz	14?
Pressure sensor	Vaisala	PTB220B	Pressure - mb	1Hz	9?
Net Radiometer	REBS	Q*7	Net radiation - W/m2	1Hz	19
Pyranometer	Kipp & Zonen	CM 21	Global shortwave radiation - W/m2	1Hz	8
Pyranometer	Eppley	PSP	Global shortwave radiation - W/m2	1Hz	25?
Pyrgeometer	Kipp & Zonen	CG4	Global longwave radiation - W/m2	1Hz	6
Pyrgeometer	Eppley	PIR	Global longwave radiation - W/m2	1Hz	10
Soil temperature sensor	REBS		Soil temperature - deg C	1Hz	>10
Heat flux plate	REBS	HFT-3	Soil heat flux - W/m2	1Hz	>10
Soil moisture	Decagon	Ech2o	Soil moisture - % vol	1Hz	10
Soil thermal properties	Hukseflux	TP01	conductivity, diffusivity, heat capacity	1Hz	9
Surface temperature sensor	Everest Interscience	4000.4ZL	Surface temp. - deg C	1Hz	10

5. Variable Names

Since many different variables can be measured at multiple sites, a naming convention, ISFF Variable Names, has been established to manage the profusion of variable names.

6. PI Interaction

We encourage our users to be involved with all aspects of the field measurements. To this end, we have a User Guide to describe all of the aspects of our field deployments.

7. Additional Online Documentation