Niwot Ridge: Carbon Dioxide Advection Study

08/01/2002 - 08/30/2002
Project Location
Niwot, Colorado

Niwot Ridge Pilot Experiment

The goals of the Niwot Ridge Pilot Experiment are:

  • To understand the significance of the horizontal transport of CO2 in the nocturnal boundary layer.
  • To study correlations between CO2 transport and surface heteorogeneity.
  • The expected results will help to better understand the global carbon balance.

Niwot Ridge: Carbon Dioxide Advection Study


This document is a standard product of NCAR/EOL which gives an overview of the measurements taken using the Integrated Surface Flux System (ISFS) and conditions during the Niwot02 field experiment. This document can be obtained in hard copy from RTF upon request.

The ISFF portion of this study is being operated as an internal development program in support of the NCAR Biogeosciences Initiative, with some support from the NCAR Director's opportunity fund. ISFF is constructing two new instrument systems for this program:

  • A TRAM system which will carry two sensor packages along a fixed cable to sample the horizontal variation of CO2 advection along a 200m transect with 1m spatial resolution. The variables to be measured are 3-component wind vector, temperature, humidity, and CO2.
  • Two Hydra systems to sample both the horizontal and vertical variation of CO2 concentration. This will augment two similar systems already deployed as part of the CU Flux Facility.

Both systems will be deployed only within the forest canopy.



At the CU Flux Facility within the CU Mountain Research Station, about 8 miles north of Nederland, Colorado. The fastest route from NCAR appears to be: (all distances approximate)

  • North on 47th to Jay Rd (1 mi)
  • West on Jay to 28th (1 mi)
  • North on 28th to Lee Hill (2 mi)
  • West on Lee Hill to Lefthand Canyon (9 mi)
  • West on Lefthand Canyon through Ward to Hwy 72 (20 mi)
  • South on Hwy 72 to "Mountain Research Station" sign (5 mi)
  • West on FR298 ~2 mi, then right at fork into MRS.
  • The site is ~2 mi up the dirt road to the north of the buildings which is gated by a combination lock. DO NOT DRIVE UP on Thurdays and Fridays. Ask a Niwot participant for detailed directions beyond the buildings.



The program is currently scheduled to run from August 1st - September 15th, 2002.

  • August 14th, 2002 - NCAR stations 1-3 (west, central, east) up and most sensors operating, except for CO2 systems.
  • September 3rd, 2002 - CO2 hydra system operational.


Measurement Sites

NCAR ISFF sensors are to be installed at three sites, roughly aligned with the existing USGS and CU towers:


Site Locations:

(These are approximate, based on my handheld GPS which appears to have large errors.)

Site Station number Latitude (N) Longitude (W)
East 3 40° 2' 2.8" 105° 32' 44.9"
NCAR 2 40° 2' 2.2" 105° 32' 52.7"
West 1 40° 2' 0.5" 105° 32' 59.0"



The layout of the sensors is shown here.

The hydra system is described in a separate report.


Niwot Data Access

The NCAR Niwot data are available for download in the following form:


Niwot Field Logbook

A computer-readable field logbook of comments noted by NCAR and other personnel is available in read-only html form and updated every day (Many people miss this important source of information - Please look here).



Project Manager:

Data Manager: