Atmospheric analysis

New Zealand lakes and ponds often have large populations of koura or freshwater crayfish.

How to use this key
Running the key
Install the Lucid Player
This key has been built with the Lucid Builder and you need the Lucid Player installed on your computer to be able to use the key. The standard edition is a free download from LucidCentral. Please use version 2.2 or later – there are some problems with earlier versions that will affect the usability of this key.
Download the key
Once you have the Player installed, you will need to get a copy of the key you wish to play.

How to use this key Running the key
Install the Lucid Player This key has been built with the Lucid Builder and you need the Lucid Player installed on your computer to be able to use the key. The standard edition is a free download from LucidCentral. Please use version 2.2 or later – there are some problems with earlier versions that will affect the usability of this key. Download the key Once you have the Player installed, you will need to get a copy of the key you wish to play.

Solar Semidiurnal Tide (S2) chart

More details on the DOBIE Wave Gauge.

Technical Note No. 98/7 - Power Management DOBIE fitted with 256k RAM data storage has two independent power supplies: a rack of 8 D-cells (Eveready alkaline No. E95, or equivalent; ~18 Ahr) mounted in the main battery compartment and a single 9V cell (Eveready alkaline No. 522, or equivalent; ~500 mAhr) mounted in a small compartment on the back of the microprocessor housing (the black box). The 9V cell is a backup supply for securing data in RAM should the main supply fail or be drained. Note that flashcard data storage is not volatile.

Technical Note No. 98/8 - Memory Management The following equations can be used to estimate memory endurance, which is the number of bursts that will fill the data memory.

Technical Note No. 98/9 - More Wave Statistics If OFFLOAD.DAT contains Task 4/0 (Wave Gauge - Wave Statistics) or Task 4/1 (Wave Gauge - Wave Statistics plus Hydrostatic Depth Spectrum) data, then the PEDP can be used to recompute the "basic" wave statistics and to compute an "extended" set of wave statistics.
Core statistics include mean water depth, standard deviation of the pressure signal, mean spectral period and spectral width. DOBIE computes these internally and they are written to OFFLOAD.DAT when data are downloaded.

Technical Note No. 98/2 - Hardware Control Options Explained: Conversion of Volts to Pressure, DOBIE Calibration, Sensor Noise Conversion of Volts to Pressure DOBIE converts volts to pressure by:
where p is pressure in pounds per square inch, V is volts output by the pressure sensor, G is gain (units of psi/volt) and O is offset (units of psi).

Technical Note No. 98/3 - Task 2 (Time Series) Explained; A Warning About "Water Depth" When deployed in still water (i.e. no waves), DOBIE experiences a total pressure that is composed of two parts: one part due to the weight of the overlying water (hydrostatic pressure) and another part due to the weight of the overlying atmosphere (atmospheric pressure). When waves are present there is yet another, fluctuating, pressure component that is due to the waves.

Technical Note No. 98/4 - Task 3 (Tide Gauge) Explained When deployed in still water (i.e. no waves), DOBIE experiences a total pressure that is composed of two parts: one part due to the weight of the overlying water (hydrostatic pressure) and another part due to the weight of the overlying atmosphere (atmospheric pressure). When waves are present there is yet another, fluctuating, pressure component that is due to the waves.

Technical Note No. 98/5 - Task 4/0 (Wave Statistics) Explained; Plus an Explanation of "Reality Checks" All wave statistics are calculated from burst time series of "hydrostatic water depth", h(t), which are related to raw pressure time series, p(t), by:
where g is acceleration due to gravity (9.81 m/s2), r is water density and F is a factor (6895 kg/[s2m]/psi) used to convert pressure in pounds per square inch to pressure in kg/(s2m). For this calculation, DOBIE assumes the water density to be 1025 kg/m3 (which is a typical seawater density).