SGP/EBBR - EBBR E4 Data Incorrect When Batt. Volt. Under 10.4 V

All data was incorrect when the battery voltage dropped below 10.4 volts.
An old battery was the cause of the problem; it had no deep cycle charge
capacity.

• Temperature of the top humidity chamber(thum_top)
• bottom vapor pressure(vp_bot)
• wind direction (relative to true north)(wind_d)
• top vapor pressure(vp_top)
• scalar wind speed(wind_s)
• base time(base_time)
• Bottom humidity(hum_bot)
• net radiation(q)
• bottom air temperature(tair_bot)
• lat(lat)
• lon(lon)
• standard deviation of wind direction (sigma theta)(sigma_wd)
• Time offset of tweaks from base_time(time_offset)
• vector wind speed(res_ws)
• Top humidity(hum_top)
• Retrieved pressure profile(pres)
• Home signal(home)
• Temperature of bottom humidity sensor chamber(thum_bot)
• top air temperature(tair_top)
• Reference Thermistor Temperature(tref)
• Dummy altitude for Zeb(alt)

• Battery(bat)
• base time(base_time)
• Reference temperature(rr_tref)
• Atmospheric pressure(mv_pres)
• Dummy altitude for Zeb(alt)
• Soil heat flow 5(mv_hft5)
• Soil temperature 1(rr_ts1)
• lon(lon)
• Left air temperature(tair_l)
• Soil temperature 4(rr_ts4)
• scalar wind speed(wind_s)
• Soil moisture 4(r_sm4)
• Left relative humidity(mv_hum_l)
• Soil temperature 3(rr_ts3)
• Soil moisture 5(r_sm5)
• Right relative humidity(mv_hum_r)
• Soil temperature 2(rr_ts2)
• Time offset of tweaks from base_time(time_offset)
• lat(lat)
• Soil moisture 2(r_sm2)
• Soil heat flow 4(mv_hft4)
• Temperature of left humidity sensor chamber(rr_thum_l)
• Signature(signature)
• Net radiation(mv_q)
• Soil heat flow 3(mv_hft3)
• Wind direction (relative to true north)(mv_wind_d)
• Soil temperature 5(rr_ts5)
• Soil moisture 3(r_sm3)
• Soil heat flow 1(mv_hft1)
• Home signal(mv_home)
• Soil heat flow 2(mv_hft2)
• Right air temperature(tair_r)
• Temperature of right humidity sensor chamber(rr_thum_r)
• Soil moisture 1(r_sm1)

• 0-5 cm integrated soil temperature, site 5(ts5)
• 5 cm soil heat flow corrected for soil moisture content, site 4(c_shf4)
• Reference Thermistor Temperature(tref)
• 5 cm soil heat flow corrected for soil moisture content, site 5(c_shf5)
• top vapor pressure(vp_top)
• lat(lat)
• h(h)
• vector wind speed(res_ws)
• Soil heat capacity 4(cs4)
• Exchange mechanism position indicator (15 to 30 min)(home_30)
• 5 cm soil heat flow corrected for soil moisture content, site 3(c_shf3)
• standard deviation of wind direction (sigma theta)(sigma_wd)
• Retrieved pressure profile(pres)
• Temperature of the top humidity chamber(thum_top)
• volumetric soil moisture, site 3(sm3)
• ratio of sensible/latent heat fluxes (Bowen ratio)(bowen)
• volumetric soil moisture, site 4(sm4)
• Soil heat capacity 3(cs3)
• Time offset of tweaks from base_time(time_offset)
• top air temperature(tair_top)
• 0-5 cm change in soil heat storage with time, site 2(ces2)
• Bottom humidity(hum_bot)
• soil heat flow, site 4(g4)
• Top humidity(hum_top)
• soil heat flow, site 1(g1)
• 0-5 cm change in soil heat storage with time, site 4(ces4)
• 0-5 cm integrated soil temperature, site 2(ts2)
• 5 cm soil heat flow corrected for soil moisture content, site 2(c_shf2)
• soil heat flow, site 2(g2)
• 0-5 cm change in soil heat storage with time, site 5(ces5)
• 5 cm soil heat flow corrected for soil moisture content, site 1(c_shf1)
• soil heat flow, site 3(g3)
• average surface soil heat flow(ave_shf)
• 0-5 cm change in soil heat storage with time, site 3(ces3)
• 5 cm soil heat flow, site 1(shf1)
• 0-5 cm change in soil heat storage with time, site 2(ces1)
• 5 cm soil heat flow, site 4(shf4)
• volumetric soil moisture, site 5(sm5)
• latent heat flux(e)
• 5 cm soil heat flow, site 2(shf2)
• wind direction (relative to true north)(wind_d)
• Temperature of bottom humidity sensor chamber(thum_bot)
• scalar wind speed(wind_s)
• bottom air temperature(tair_bot)
• 0-5 cm integrated soil temperature, site 3(ts3)
• Soil heat capacity 2(cs2)
• Soil heat capacity 5(cs5)
• Exchange mechanism position indicator (0 to 15 min)(home_15)
• net radiation(q)
• 5 cm soil heat flow, site 3(shf3)
• bottom vapor pressure(vp_bot)
• 0-5 cm integrated soil temperature, site 4(ts4)
• soil heat flow, site 5(g5)
• lon(lon)
• 5 cm soil heat flow, site 5(shf5)
• Dummy altitude for Zeb(alt)
• Soil heat capacity 1(cs1)
• volumetric soil moisture, site 1(sm1)
• 0-5 cm integrated soil temperature, site 2(ts1)
• base time(base_time)
• volumetric soil moisture, site 2(sm2)

SGP/EBBR/E4 - Reprocess: Soil Moisture Probe Low at Times

On 18 June 1996, soil moisture probe 5 data reduced to a very low level.  
At 0000 GMT on 19 June 1996 the soil moisture indicated below zero, which 
is not physically possible.  Over the next few months the soil dried to a 
low enough moisture level that the output again went too low.  The qc 
minimum limit of 0 will indicate these times.  The output recovered to 
reasonable values on 1 July at 2100 GMT.  It again went low on 4 
July at 0100 and remained that way until at least 8 July.  No data is 
available from 9 July to 24 July to allow us to see the behavior during 
that period.  On 27 July, at 0330 GMT, the output was very high (113.8) for 
some unknown reason.  The output also went offscale at 0000 on 3 August, 
for an unknown reason.  The output again went low at 0800-1530 GMT on 10 
September and 0000 GMT on 11 September through 0900 GMT on 15 September.  No 
incorrect values have occurred since.  However, it is clear that at very 
low soil moisture, probe 5 indicates lower than normal.  It will be replaced 
when a spare is available.  

Affected data are:

15 minute: r_sm5

30 minute: sm5, c_shf5, g5, cs5, ces5, ave_shf, e, h

• Soil moisture 5(r_sm5)

• Soil heat capacity 5(cs5)
• 0-5 cm change in soil heat storage with time, site 5(ces5)
• soil heat flow, site 5(g5)
• latent heat flux(e)
• 5 cm soil heat flow corrected for soil moisture content, site 5(c_shf5)
• h(h)
• average surface soil heat flow(ave_shf)
• volumetric soil moisture, site 5(sm5)