PRELIMINARY.

Introduction

This document is a standard product of NCAR/ATD/SSSF which gives an overview of the measurements taken by ISFF and conditions during the TBLMTN98 field experiment. This document can be obtained either in hard copy from SSSF or in electronic form from the NCAR/ATD WWW site.

Data Access

The NCAR data for TBLMTN will be available in only 1 form:

5-minute averages of first and second-order moments of calibrated data. We recommend combining these to obtain more statistically-significant averages over longer time periods. These are available in NetCDF format data files. Contact SSSF if you need to access the data in a different format (e.g. ASCII).

Also available is a computer-readable logbook of comments noted by SSSF personnel. Direct ASCII output from the sonic anemometer will be captured by the investigator occasionally, as needed.

The NetCDF statistics are available online here, after the data processing steps noted below. Please contact The ATD Data Manager if you plan to work with these data, so that we can inform you of any updates to this data set.

A complete list of variables is available. This list shows the NetCDF variable name, dimensions, descriptive variable name, units, and additional comments, if available. Each file contains all the statistics for one day, beginning at 00:00:00 UTC. All variables are dimensioned (time), where time is in 5 minute increments (288 per day).

Most descriptive variable names hopefully are self-explanatory. Those beginning with Capital letters came from slow response sensors and those with lower cases letters from fast response sensors. Higher order statistics are indicated by products of variables. For example, w'tc' is the covariance between vertical velocity and sonic virtual temperature and h2o'h2o'h2o'h2o' is the fourth order moment of water vapor mixing density.

Location

The PAM station was deployed near the center of Table Mountain, about 6 miles north of Boulder. The boom for the sonic anemometer was oriented nearly West with the solar panels to the ENE of the tower tripod, about 9m away. The rain gauge was about 2m to the NW of the solar panels. The Licor radiometer was on one of the supports for the rain gauge wind screen.

Photographs will be taken at a later date.

Sensors

The NCAR sensors are mostly described in the ASTER Facility Description.

Data Usage/Processing Notes

To be completed later.

Daily Weather Plots

The following plots summarize conditions measured by the NCAR sensors for each day of the project. Each plot covers one days (00-23 CDT) and is labeled with time in GMT at the bottom and local time (CDT) at the top. The top panel displays temperature and specific humidity measured at 2m, pressure, and precipitation rates (if present). Below that is a plot of wind speed and direction measured at 10m, with a dotted line showing the direction of the best fetch (West). The next panel shows solar radiation, sensible and latent heat flux. The bottom panel shows the Monin-Obukhov stability parameter, z/L, the friction velocity, u*, and the Bowen ratio calculated from the flux data. Since these fluxes and derived parameters are based on smoothed, 5-minute average statistics, they should not be used quantitatively and are only shown for guidance in selecting periods to analyze further.

November
18 19 20 21
22 23 24 25 26 27 28
29 30 . . . . .

December
1 2 3 4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31 . .

January
1 2
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31 . . . . . .

November
			18	19	20	21
22	23	24	25	26	27	28
29	30	.	.	.	.	.

December
		1	2	3	4	5
6	7	8	9	10	11	12
13	14	15	16	17	18	19
20	21	22	23	24	25	26
27	28	29	30	31	.	.

January
					1	2
3	4	5	6	7	8	9
10	11	12	13	14	15	16
17	18	19	20	21	22	23
24	25	26	27	28	29	30
31	.	.	.	.	.	.

Other plots

None yet.