• Likely a BNO055

• Determines albedo by comparing values between the Pyranometer and Pyrgeometer
  • Could potentially make life easier by just having two dedicated thermopile sensors?
• Must ensure that solar radiation does not affect the Pyrgeometer during sunset and sunrise

• Deduce from barometer or GPS?

• Measures wind speed and direction
• Probably use 3 or 4 barometers to detect air pressure on different sides of sensor array
  • Would be better to use ultrasonic or microwave for better harsh weather survival
• Will probably need housing behind hydrophobic membranes, or use IP67 MEMS chips
• If possible, also detect vertical wind speed - to determine Eddy covariance flux, which can be used for Atmometer calculations

• Measures rate of evaporation to atmosphere
• Can be estimated mathematically
• Useful to determine how much watering is needed for crops

• Measures atmospheric pressure
• Also investigate QNH = atmospheric pressure adjusted to sea level

• Detects nuclear denotations (optical, x-ray, infrasound, etc)
• We extend concept to detect anything that makes a bang (car backfire, lightning, gunshot...)

• Measures incident EM radiation
• Variants can be used to measure microwave radiation
• See also: Radiometer

• Measures height of cloud base
• Can possibly be roughly derived from dew point
  • cloud base from dew point & temp
  • cloud alt & temp from dew point & temp

• Measures angle above/below horizon
• Useful for initial setup, and also hand-held use
• Uses the IMU

• Operates during twilight (sunrise, sunset)
• Measures particulate at different layers of atmosphere just above earth shadow
• Can more info be gained via the spectrometer?

• Measures ionising radiation
  • alpha; sensor must be exposed to external environment
  • beta; sensor must not be obstructed by metals
  • gamma; sensor must not be obstructed by dense materials
  • muons; doesn't matter where sensor is
• Note: Upper UV wavelengths are also ionising, see UV radiometer below

• Tdb, can be measured using a normal thermometer freely exposed to the air but shielded from radiation and moisture.

• A photometer specifically tuned to light frequencies and heuristics of flames
• Can optically detect fire up to (unknown) range, quicker than particulate sensors
• Some false-positive issues

• Useful for detecting risk of forest fires

• Detects approximate direction and range of CG/GC lightning strikes
• Unreliable for detecting IC/CC lightning
• Must not be EM shielded
• Maybe also do optical lightning flash check?

• Likely a MTK3339 v3 or above

• Likely a BNO055

• Calculate

• Determines duration and intensity of sunlight
• bright sunshine hours - test every 36 seconds for specific criteria:
  • Sunshine duration is defined by WMO as the time during which the direct solar radiation exceeds the level of 120 W/m².
• Global solar intensity
• Could be derived from Pyranometer and/or Heliospectrometer

• Spectrometer that points at sun
• Determines amount of optically active aerosol particles and gaseous constituents in atmosphere
• Ideally also monitor PAR - Photosynthetic Active Radiation
• Will likely incorporate Pyranometer

• Movable platter of sensors that tracks the sun
• Needs to be x and y axis movement, eg. to track Analemma
• Azimuth (Sun) Tracker
• Determines location of the sun and points instruments at it, like sunflowers face the sun
• Will require moving parts unless better solution can be found :/
• May require Monochromators
• Required for: Heliophotometer, Heliospectrometer, Pyrheliometer and Pyranometer

• Also known as psychrometer, humidity
• Measures water vapour (humidity) in atmosphere
• Sensor requires access to atmosphere (ie. no hydrophobic membrane)

• Replaces red channel of normal photo with NIR
  • Why not replace green channel? That way, the greener a plant, the more growth. ;)
• Shows plant growth easily (video)

• Likely a BNO055

• ~Specific Humidity
• Calculate saturated & actual

• Measure light pollution at night

• Qualifies cloud cover
• During daytime, thermopiles can be used (apparently these work at night too?!)
• At night, a Seebeck TEG sandwiched between two metal plates could be used

• Measures solar radiation
• Likely components would result in wider range of wavelengths examined (Solar Spectral Flux Radiometer)
• See also: Heliophotometer, Heliospectrometer

• Like a Pyranometer, but ground facing
• Must ensure sunlight at sunrise and sunset doesn't interfere with it
• See also: Abledometer

• Measures direct beam solar irradiance
• Points directly at sun
• Likely part of the Heliospectrometer

• Determines dew point
• Can be derived from RH and temperature
  • Alternative calculation (PDF)
  • Code

• Measures acoustic noise pollution
• A specialised sound level meter

• Determines composition of target substance - there will be two of them:
  • Liquids/Solids - a sensor at top of array that can be pointed (when handheld) at target substance
    • Just re-use the heliospectrophotometer with an IR light source next to it?
  • Gas (air) - a sensor inside array that inspects air flowing through the sensor
• Need to work out how to calibrate

• Measures azimuth, horizon and elevation.
• Useful when mounting sensor in fixed location, or hand-held mode
• Uses IMU sensors

• Infrared images

• Measures heat
• There will be a whole bunch of these, often built in to other sensors

• Measures UVA and UVB
• Likely need sky and ground facing sensors

• Can be calculated (PDF)
  • Code
• Info about WBT

• Useful for predicting frostbite risk

Not sure if initial version will have these as they are difficult to implement and/or power...

• Like an omnidirectional PIR, but with radar, rage = ~4m
• Can't "see" through glass
• Useful for animal detection (but current options can't directionally locate)

• Can determine height and velocity of clouds using two fisheye cameras
  • Cameras need to be >300m apart based on existing research = problem
• Compares two fisheye sky images to determine altitude
• Compares images after short delay to determine velocity

• Measures drop size, distribution/spacing and velocity of hydrometeors (rain, hail, etc).
• See also: Pluviometer

• Sensors found so far are quite big (most the size and shape of a leaf, or bigger)
• The whole concept of leaf wetness is borken. Instead of trying to make leaf-shaped sensors, there should be a standard (simple!) generic sensor (maybe with a few angles and textures) to measure evaporation, and then work out how that relates to different plants on a species by species basis.

• Detects microwave-reflective objects up to 16 metres away
• Works in harsh conditions, including zero visibility

• Determine amount of particulate suspended in the air
• Would need special (often large in size and power consumption) sensor for PM10 and PM2.5
• Could potentially use TOF camera for larger particles?
• PM Sensor
• Dust sensor

• Also known as: Ombrometer, Udometer, Rain guage
• Measures precipitation intensity by weight
• Could use something akin to Pythagoras cup (which is is actually a Tantalus cup), or determine based on readings from disdrometer?

• Measures changes in refractive index of the atmosphere (Cn2)
• With additional sensors can calculate sensible heat flux and latent heat flux (evapotranspiration)
• Could potentially use TOF camera to remove need for remote receiver?

• Probably do this as later upgrade or addon?
  • will need FPGA
  • will chew power and generate lots of heat
  • will need lots of active telemetry
• General radio spectrum scanning
• Aircraft tracker: Mode-S / ADS-B / MLAT signal reader
• Ship tracker: AIS
• Are there simpler ways to do aircraft and ship tracking?

Note: Ground-based sensors listed below could potentially be merged in to one device to minimise power, processing and telemetry complexity

• Measures earth movements (eg. earthquakes)
• Ideally requires a Geophone
• Probably want this as separate add-on module?
  • Use accelerometer as rudimentary seismometer if not present?

• Add-on remote sensor
• A tube with humidity/pressure/temp sensors to determine actual evaporation from soil

• Add-on remote sensor
• Measures soil moisture

• Add-on remote sensor
• Measure soil pH

Note: Following liquid sensors could be combined in to single unit?

• Measures particulate in liquids

• Add-on remote sensor
• Measure liquid pH

• Measures rate of flow of liquid

• Including non-contact