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Enabling better global research outcomes in soil, plant & environmental monitoring.

ATMOS 14 Temp & Humidity

Relative Humidity, Barometric Pressure, Air Temperature, and Vapor Pressure with or without a passive radiation shield.

Use the rugged ATMOS 14 sensor with soil moisture probes in microclimate and evapotranspiration studies.

Note: The Decagon VP-4 has been replaced by the Meter ATMOS 14.

Microclimate measurement made simple

If you’re doing a microclimate or evapotranspiration study, you may need up to four extra sensors to get important measurements that will benchmark your data. Not to mention you have to face the hassle of getting all those sensors integrated into your system. What you need is something simpler. With this in mind, we engineered the ATMOS 14 to be four sensors in one—air temperature, relative humidity, barometric pressure, and vapour pressure.

With the ATMOS 14, all your bases are covered

Thousands of engineers and ecologists already depend on the ATMOS 14 for straightforward measurements. Whether you’re using the EM60G to look at plant emergence, leaf area index, or fractional interception, there isn’t an easier way to benchmark your data. The ATMOS 14 is a versatile, and fast sensor designed to make taking temp/RH measurements simpler and therefore less work.

Plug it in, and walk away

Despite its minimalist design, the ATMOS 14 provides maximum value. While other sensors require wiring and programming, the ATMOS 14 simply plugs into the EM60G (It’s also compatible with third-party data loggers). There’s no having to figure out complicated instructions. Just mount the sensor on your data logger mast, plug it in, and walk away.

Measures a lot. Requires very little effort.

The ATMOS 14 gives accurate vapour pressure and RH without a lot of cleaning. Plus it’s weatherproof, meaning it will last a long time in the field. Another helpful feature is the compact shape that fits into tight spaces, leaving room on a mast for other sensors.

Readings don’t get any more rapid

Because the ATMOS 14 is plug and play, setup is quick. And responses are equally fast. Thanks to a Teflon protection screen that keeps liquid water out, but vapour moving freely through, it responds rapidly while keeping dust and liquid water off the sensor. Both features add up to time saved on your part.

For everything it measures, there’s not much to it

With ATMOS 14, all your basic microclimate measurements are covered using a small, simple integrated sensor. This versatile, low-maintenance sensor will rapidly and reliably measure air temperature, relative humidity, barometric pressure, and vapour pressure, making benchmarking quick and hassle-free.


Utilising weather sensors in a custom IoT (Internet of Things)

The ATH-2S Temperature & Humidity sensor is available in a preconfigured IoT (Internet of Things) setup for continuous real-time temperature and humidity monitoring.

Alternatively, we recommend the SNiP-WS24 which integrates 1x MFR-NODE with three sensors: to a site’s unique network, communication and power requirements: 1x AWS200 Automatic Weather Station, 1x ATH-2S Ambient Temperature & Humidity (SDI-12) Sensor and 1x PRP-02 Professional Tipping Bucket Rain Gauge. The MFR-NODE can support additional sensors. With theses combined, multiple atmospheric parameters can all be continuously measured in real-time including: Wind Speed, Direction & Gust Speed, Air Temperature, Relative Humidity, Barometric Pressure and Vapour Pressure.

SDI-12 Compatible

Integrate into non-Decagon data loggers with the easy-to-use SDI-12 communication protocol.


This 5 cm x 2 cm sensor is able to fit into the smallest of spaces.


Thanks to its unique Teflon screen, the relative humidity sensor can survive a deluge. Naturally, it won’t be transmitting accurately while waterlogged; but as soon as it has dried out, it’s back in the game.

Fast Response

The Teflon screen protects the sensor from liquid water and dust without limiting diffusion of water vapour. The protected sensor is still able to quickly respond to changes in humidity.

Integrated Temperature for Accuracy

Accurate relative humidity readings require accurate air temperature readings taken at the same place and time. This sensor takes both measurements simultaneously for the best possible accuracy.

Radiation Shield Included

The included radiation shield is designed to improve air temperature readings by minimising radiation and maximising airflow over the surface of the sensor. Specially designed to preserve the correlation between actual air temperature and sensor air temperature while keeping the shield size small.

RANGE 0 to 100% RH
ACCURACY Sensor measurement accuracy is variable across a range of temperatures.
Refer to the chart in Figure 1 to determine the accuracy specification for the ATMOS 14 sensor.
(τ, 63%):
< 40 s (response time in 1 m/s air stream)
HYSTERESIS < 1% RH typical
LONG TERM DRIFT < 0.5% RH/year typical
RANGE -40°C to 80°C
ACCURACY Sensor measurement accuracy is variable across a range of temperatures. Refer to the chart in Figure 2 to determine the accuracy specification for the VP-4 sensor
(Τ, 63%)
< 400 s (response time in 1 m/s air stream)
LONG TERM DRIFT < 0.04°C / year typical
RANGE 0 to 47 kPa
ACCURACY Sensor measurement accuracy is variable across a range of temperatures and RH. Refer to the chart in Figure 3 to determine the accuracy specification for the VP-4 sensor.
RANGE 49 to 109 kPa
DIMENSIONS 1.96 cm (dia) x 5.4 cm (h)
POWER REQUIREMENTS 3.6 to 15 VDC, 0.03 mA quiescent, 4 mA during 300 ms measurement
OUTPUT Decagon Digital or SDI-12
CONNECTOR TYPES 3.5 mm (stereo) plug or stripped and tinned lead wires (pigtail)
CABLE LENGTH 5 m standard; custom cable length available upon request
Meter/Decagon: Em50 Series (Firmware 2.19+)
ICT SDI-12 logger, AML, AWS, Universal Telemetry Hub
Campbell Scientific: Any logger with serial I/O
DataTrac (rev 3.11+)

VP4 Humidity Acc

VP4 VP Acc

Temperature Acc VP4