This web page is linked to by the main ROOF web page, at ROOF, and is devoted to photographs of equipment at the ROOF site in Santa Barbara, CA for the 2001 June stratus observations.

The site is at 200 feet ASL, and has a good view of all horizons.

Figure 1.  View of access to roof, looking east. Note the cable going through the door window to the roof.  The orange tree on the left "houses" the temperature and pressure StowAway units.

Figure 2.  Looking north, showing a horizon about 7 degrees high.  Note the cinder blocks on wood L-brackets for securing the daiometer boxes during wind.

Figure 3.  Looking south, showing a good horizon except for a swamp cooler.  The MTP radome is in the foreground.

Figure 4.  Looking Northeast.

Figure 5.  Same room after installing the radiometers, cables and computers.

Figure 6.  Looking west at the Radio Shack temperature sensor white box, suspended from a cable.

Figure 7.  Looking north at the Taylor temperature sensor white box, mounted atop a pole.

The previous two pictures show my effort to improve the quality of ambient air temperature measurements.  It was motivated by a frustrating attempt to determine hot target emissivities.  The white boxes are made of 1/4-inch thick posterboard, white on both sides.  The sensor is suspended within an upside down yogurt cup (empty), to provide an added barrier to sunlight entering the sensor area (the yogurt cup by itself was inadequate).

On June 11 an Omega 530HR IR radiometer arrived at the ROOF site.  The passband is supposed to be 8-14 microns, which implies a long look distance and partial transparency when viewing zenith.  The lowest temperature reading is -30 C, so only low elevation angles (for CLR conditions) will register.  An emissivity setting of 100% will be used for measurements of the atmosphere.  The reception pattern is approximately circular with a diameter of 2.9 degrees.  The IR radiometer is a hand-held unit, though it has a camera tripod bold mounted at the base of the handle.  Although it operates with 4 AA batteries, it can also be powered with a 6 volt, 300 milliamp power supply.  An analog output connection can be used to record temperatures with a scale of 1mV/degree C.

Figure 7a.  View of the Omega 530HR IR radiometer from inside the "sun room."  It is mounted to 1/4-inch thick posterboard with an aperture for viewing the sky unobstructed by window or screen material.  A digital level is mounted atop the radiometer.

The digital level has 0.1 degree resolution on readouts, and has been collimated with the IR radiometer pointing groove.  Between the top of the radiometer and the digital level is a pointing groove which allows a view of the scene sampled by the radiometer.  A posterboard "wedge" can be slid from its full up position (shown), corresponding to viewing an elevation angle of 0.0 degeres, to lower positions corresponding to elevation angles of up to 8.0 degrees.  Higher elevation angle readings will require that the unit be removed from this mounting location (by unfastening bungee connectors from eye bolts) and going outside for manually scanning.

Figure 7b.  View of east horizon, with a 2.9-degree circle representing the "reception beam" of the IR radiometer.  The center of the circle is at an elevation of about 2.4 degrees.  The white boxes for the in situ OAT sensors are in the foreground.

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This site opened:  May 31, 2001.  Last Update:  June 12, 2001