Thursday, April 26, 2018

24-hour Photometer for NearSys Station

I ran both the 7-channel LED photometer and a UV-B photometer all day April 25th. This time, there was no unexpected blue spike at around sunrise.

It can be seen there was an event at 12:00 and 15:30 that briefly dimmed the solar flux. It can also be seen that I need to align the charts of the two datasets a little more carefully.

Results from the LED Photometer

Results from the AdaFruit UV-B Photometer

Monday, April 23, 2018

Garden Soil Temperature

I ran an experiment to see how my garden's temperature varies. To do this, I buried two sets of dataloggers and shot several readings with my Seek Reveal thermal imager.
At the top is the munched dual temperature logger and bottom right is the unmulched logger. Both have LM335 temperature sensors buried 2" and 5" deep.

The Seek Reveal shows there is a wide variation in surface temperatures because if the play of sunlight and shadows on an uneven soil surface. The imager is only measuring the surface temperature, not the temperature below the surface.

The Seek Reveal shows just how strongly undulations affect the surface temperature.

The below surface temperatures show what I expected. The deeper temperature doesn't experience as large of a temperature swing. Also, mulching reduces the magnitude of the temperature swing that soil experiences.

Soil that's not covered by 2" of mulch experienced a stronger temperature swing over 22 hours than did munched soil. Also, munched soil didn't experience of a temperature difference between 2" and 5" deep.



24 Hour Photometer at NearSys Station, 22 April 2018

After posting photometer last night, I got to thinking that I had no good way to compare data from week to week. I think however, that collecting for 24 hours get give me this capability. So I'm posting my first 24 hour photometer run.

I need to fix the red LED and add ultraviolet data (I am running a test with a BalloonSat Mini flight computer - it won't father as much data as my LED Photometer).

Interesting, blue light spikes in intensity at sunrise. I need to see if this is a typical event.


Sunday, April 22, 2018

24 Hour Temperature and Relative Humidity at NearSys Station, 21 April 2018

Data was collected using the Amprobe 200. Without realizing the issue, it was prigrammed for a maximum temperature of 100 deg F. The resulting chart illustrates why the maximums need to be removed from the datalogger during programming and why it needs its sunshield. The air temperature did not exceed 100 degs on Saturday.


All Sky Photometer for NearSys Station, 21 April 2018

The sky was clear all day at NearSys Station.


UAVSonde Data for NearSys Station, 20 April 2018

The UAVSonde collected data at 8:30 PM.

The ground temperature was 67.0 deg F and the relative humidity was 24.7%. At FL4 (400 feet AGL) the temperature was 66.9 deg F and the relative humidity was 19.1%.

The visibility was determined to be in excess of 50 miles.

Looking east

Looking north

Looking south

Looking east


Sunday, April 15, 2018

All Sky Photometer for NearSys Station, 15 April 2018

We had a good mix of sunny and cloudy skies at NearSys Station today. That is apparent in the all sky photometer chart.

Cloud Altitude Estimate for NearSys Station, 15 April 2018

According to the thermal imager, the stratus overcast at NearSys Station has a temperature of 11 degrees while the ground has a temperature of 42 degrees. According to the weather station, the air temperature is 66 degrees and the dew point is 36 degrees.

The temperature difference in the thermal imager data is 31 degrees and 30 degrees in the weather station data. Assuming a dry adiabatic lapse rate of 5.4 degrees per 1,000 feet, the cloud height is between 5,700 and 5,600 feet. That's a pretty good agreement.


Friday, April 13, 2018

UAVSonde Data for NearSys Station, 13 April 2018

The UAVSonde carried a temperature logger to flight level 4 at 5:30 PM MST (I made a mistake and didn't attach the temperature AND relative humidity datalogger).

The temperature on the ground was 57.5 deg and the air temperature at FL4 was 52.8 deg.

Visibility for NearSys Station, 13 April 2018

The UAVSonde recorded images from flight level 4 at 5:30 PM MDT. The images indicate the visibility is in excess of 50 miles. It was a bit windy, probably more so aloft. So the UAV needed to pitch or roll to maintain position.

Looking north.

Looking east.

Looking south.

Looking west.

Tuesday, April 10, 2018

All Sky Photometer for NearSys Station, 10 April 2018

It's been a cloudy day, although the sky can be seen to have brightened briefly in the late afternoon.


Monday, April 9, 2018

24 Hour Temperature and Relative Humidity at NearSys Station, 8 April 2018

The Amprobe TR200-A recorded the temperature and relative humidity once per minute for 24 hours. These are measurements taken on the front porch to make sure the unit didn't get wet.

Interesting how the relative humidity shot up after 4:00 PM MST.


Sunday, April 8, 2018

UAVSonde Data for NearSys Station, 8 April 2018

The UAVSonde was launched at around 4:00 PM MDT. The winds were higher than typical, so the UAV pitched into the wind to remain on station.

Conditions on the ground,
Temperature: 60.8 F
Relative Humidity: 31.6%

Conditions at 400 feet AGL,
Temperature: 55.0 F
Relative Humidity: 36.6%

The visibility was barely 50 miles.

Looking east, notice the swirl in the clouds. This mild storm added some wind during this flight.

Looking north

Looking south

Looking west

Saturday, April 7, 2018

Cloud Altitude Measurement, 7 April 2018

NearSys Station is experiencing 100% overcast with nimbostratus. The image beyond shows what this cloud cover looks like.

The important part of this image to note is the bright trapizoid in the middle.

The next two thermal images show the temperature appearance of the clouds.

The bright white trapizoid is 25 degrees F. You'll notice that's three degrees warmer than the surrounding, clouds

The darker portion of the cloud is warmer, therefore lower.

The relative humidity at NearSys Station is 64% and we are getting occasional light drizzle. Therefore, I believe it's more accurate to assume a wet adiabatic lapse rate closer to 3.0 degrees per 1,000 feet.

The ground temperature, according to the thermal imager is 46 degrees. According to the weather station, the air temperature is 50 degrees and the dew point is 62 degrees.

Assuming a wet adiabatic lapse rate, the cloud height is either 6,000 feet according to the thermal imager or 4,000 feet according to the weather station. Also, the difference in height between the lower dark portion of the cloud and its brighter upper portion is 1,000 feet. This also indicates the darker portion of the nimbostratus is the lower hanging part.

The clouds are drifting at a angular speed of 0.5 degrees in 4 seconds (this was a tough measurement to make since I was using the sun as a reference. Taking the average height, I estimate the wind is blowing at 7.5 MPH at 5,000 feet AGL.

Tuesday, April 3, 2018

Cloud Height Estimation for NearSys Station, 3 April 2018

NearSys Station was 100% overcast with stratus, altostratus I believe. The sun wasn't visible through the clouds, but it did create a brightened circle.

The thermal imager reported the ground temperature was 42 F and the cloud temperature was -5 F. The weather station reported the air temperature was 56 F and the dew point was 23 F. Assuming a dry adiabatic lapse rate of 5.4 degrees per 1,000 feet, the cloud height was between 6,100 and 8,700 feet.

Thermal image of the altostratus over NearSys Station. More detail is visible in long-wave infrared.

Visible image of the same clouds

Monday, April 2, 2018

Temperature and Relative Humidity for NearSys Station, 2 April 2018

The Amprobe TR200 recorded the temperature and relative humidity every minute for 24 hours. The location was the front porch, so the recorded temperature is a little warmer than out in the yard.


Sunday, April 1, 2018

All Sky Photometer, NearSys Station 1 April 2018

NearSys Station experienced a cloudy day with brief sunshine in the evening. The Photometer chart shows its lack of direct sunlight.


Cloud Data at NearSys Station, 1 April 2018

It's overcast at NearSys Station, we are experiencing 100% stratus. Below are the data collected this morning and my conclusions.

The thermal imager reports a ground temperature of 28 F and cloud temperature of 10 F. The weather station reports the air temperature us 45 F and the dew point is 36 F.

Taking the temperature difference and assuming an adiobatic lapse rate of 5.4 degrees per 1,000 feet, derives the following altitudes for our straits overcast.

Thermal Imager: 3,000 feet
Weather Station: 1,700 feet

Thermal image of the stratus overcast

Visible image of the stratus overcast





Visibility for NearSys Station, 1 April 2018

The UAVSonde was launched at 9:00 AM MST. Based on the images recorded, the visibility is at least 50 miles.

Looking north

Looking west

Looking south

Looking east. The Boise Mountains are visible on the left side of the image.

UAVSonde Data, 1 April 2018

The UAVSonde was launched at 9:00 AM MST. It reported the following data.

On the ground,
Air Temperature: 50.8 F
Relative Humidity: 58.0%

At 400 feet AGL,
Air Temperature: 43.3 F
Relative Humidity: 58.2%