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Improved depthPP for the case when only one P sensor is available. Be…
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…fore, the same displacement seen on the nearest P sensor from its nominal depth was applied to the current sensor. Now we take into account the site nominal depth in order to locate the current sensor. The current limitation is that the tidal amplitude is flattenned (the actual site depth varies with time != site nominal depth).
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@ggalibert
ggalibert committed Aug 29, 2017
1 parent a96fa0b commit efd7e97
Showing 1 changed file with 58 additions and 35 deletions.
93 changes: 58 additions & 35 deletions Preprocessing/depthPP.m
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Original file line number Diff line number Diff line change
Expand Up @@ -81,6 +81,7 @@
% check wether height or target depth information is documented
isSensorHeight = false;
isSensorTargetDepth = false;
isSiteTargetDepth = false;

if isfield(sample_data{1}, 'instrument_nominal_height')
if ~isempty(sample_data{1}.instrument_nominal_height)
Expand All @@ -94,6 +95,18 @@
end
end

if isfield(sample_data{1}, 'site_nominal_depth')
if ~isempty(sample_data{1}.site_nominal_depth)
isSiteTargetDepth = true;
end
end

if isfield(sample_data{1}, 'site_depth_at_deployment')
if ~isempty(sample_data{1}.site_depth_at_deployment)
isSiteTargetDepth = true;
end
end

% read options from parameter file
depthFile = ['Preprocessing' filesep 'depthPP.txt'];
same_family = readProperty('same_family', depthFile, ',');
Expand Down Expand Up @@ -161,7 +174,7 @@
useItsOwnPresRel(iCurSam) = readDatasetParameter(sample_data{iCurSam}.toolbox_input_file, currentPProutine, 'useItsOwnPresRel', useItsOwnPresRel(iCurSam));

% look for nearest instruments with depth or pressure information
if ~isProfile && (isSensorHeight || isSensorTargetDepth)
if ~isProfile && (isSensorHeight || isSensorTargetDepth) && isSiteTargetDepth
% let's see if part of a mooring with pressure data from other
% sensors
for iOtherSam = 1:nDatasets
Expand Down Expand Up @@ -312,9 +325,9 @@
else
if ~isProfile
fprintf('%s\n', ['Warning : ' sample_data{iCurSam}.toolbox_input_file ...
' please document either instrument_nominal_height or instrument_nominal_depth '...
' please document site_nominal_depth or site_depth_at_deployment and either instrument_nominal_height or instrument_nominal_depth '...
'global attributes so that an actual depth can be '...
'computed from other pressure sensors in the mooring']);
'computed from 1 or 2 other pressure sensors in the mooring']);
end
continue;
end
Expand Down Expand Up @@ -556,7 +569,7 @@
else
% if no pressure data, try to compute it from other sensors in the
% mooring, otherwise go to next sample data
if isSensorHeight || isSensorTargetDepth
if (isSensorHeight || isSensorTargetDepth) && isSiteTargetDepth
if isempty(nearestInsts{iCurSam})
fprintf('%s\n', ['Warning : ' descSam{iCurSam} ...
' has no neighbouring pressure sensor on this mooring from ' ...
Expand All @@ -566,10 +579,11 @@
iFirst = firstNearestInst(iCurSam);
iSecond = secondNearestInst(iCurSam);

if iSecond == 0 && iFirst ~= 0
if iSecond == 0 && iFirst ~= 0
tidalAmplitudeComment = ' Tidal amplitude is not accurate.';
fprintf('%s\n', ['Warning : ' descSam{iCurSam} ...
' has its actual depth inferred from only one neighbouring pressure sensor ' ...
'on mooring']);
'on mooring.' tidalAmplitudeComment]);
% we found only one sensor
presIdxOther = getVar(sample_data{nearestInsts{iCurSam}(iFirst)}.variables, 'PRES');
presRelIdxOther = getVar(sample_data{nearestInsts{iCurSam}(iFirst)}.variables, 'PRES_REL');
Expand All @@ -593,55 +607,64 @@
'precision at a deployed depth)'];
end

% compute pressure at current sensor assuming sensors
% repartition on a vertical line between current sensor
% and the nearest. This is the best we can do as we can't
% have any idea of the angle of the mooring with one
% pressure sensor (could consider the min pressure value
% in the future?).
%
% computedDepth = depthOther + distOtherCurSensor
% computedHeight = heightOther - distOtherCurSensor
%
% vertical axis is positive down when talking about
% depth
% compute pressure at current sensor using trigonometry and
% assuming sensors repartition on a line between the
% nearest pressure sensor and the mooring's anchor
%
% the only drawback is that tidal amplitude is
% flattenned by static value of siteDepth
if isfield(sample_data{iCurSam}, 'site_nominal_depth')
if ~isempty(sample_data{iCurSam}.site_nominal_depth)
siteDepth = sample_data{iCurSam}.site_nominal_depth;
end
end

if isfield(sample_data{iCurSam}, 'site_depth_at_deployment')
if ~isempty(sample_data{iCurSam}.site_depth_at_deployment)
siteDepth = sample_data{iCurSam}.site_depth_at_deployment;
end
end

if isSensorTargetDepth
distOtherCurSensor = sample_data{iCurSam}.instrument_nominal_depth - sample_data{nearestInsts{iCurSam}(iFirst)}.instrument_nominal_depth;
signOtherCurSensor = sign(distOtherCurSensor);

distOtherCurSensor = abs(distOtherCurSensor);
nominalHeightOther = siteDepth - sample_data{nearestInsts{iCurSam}(iFirst)}.instrument_nominal_depth;
nominalHeightCurSensor = siteDepth - sample_data{iCurSam}.instrument_nominal_depth;
else
distOtherCurSensor = sample_data{nearestInsts{iCurSam}(iFirst)}.instrument_nominal_height - sample_data{iCurSam}.instrument_nominal_height;
signOtherCurSensor = -sign(distOtherCurSensor);
% 0 => two sensors at the same depth
% 1 => current sensor is deeper than other sensor
% -1 => current sensor is lower than other sensor

distOtherCurSensor = abs(distOtherCurSensor);
nominalHeightOther = sample_data{nearestInsts{iCurSam}(iFirst)}.instrument_nominal_height;
nominalHeightCurSensor = sample_data{iCurSam}.instrument_nominal_height;
end

% theta is the angle between the vertical and line
% formed by the sensors
%
% cos(theta) = heightOther/nominalHeightOther
% and
% cos(theta) = heightCurSensor/nominalHeightCurSensor
%
% computedDepth = nominalSiteDepth - nominalHeightCurSensor * (nominalSiteDepth - zOther) / nominalHeightOther
%
% pressure = density*gravity*depth
%
if ~isempty(sample_data{iCurSam}.geospatial_lat_min) && ~isempty(sample_data{iCurSam}.geospatial_lat_max)
% compute depth with Gibbs-SeaWater toolbox
% depth ~= - gsw_z_from_p(relative_pressure, latitude)
if sample_data{iCurSam}.geospatial_lat_min == sample_data{iCurSam}.geospatial_lat_max
zOther = - gsw_z_from_p(relPresOther, sample_data{iCurSam}.geospatial_lat_min);
computedDepthComment = ['depthPP: Depth inferred from only one neighbouring pressure sensor ' ...
descOtherSam{iCurSam}{iFirst + 1} ', using the Gibbs-SeaWater toolbox ' ...
'(TEOS-10) v3.06 from latitude and ' presComment '.'];
'(TEOS-10) v3.06 from latitude and ' presComment '.' tidalAmplitudeComment];
else
meanLat = sample_data{iCurSam}.geospatial_lat_min + ...
(sample_data{iCurSam}.geospatial_lat_max - sample_data{iCurSam}.geospatial_lat_min)/2;
zOther = - gsw_z_from_p(relPresOther, meanLat);
computedDepthComment = ['depthPP: Depth inferred from only one neighbouring pressure sensor ' ...
descOtherSam{iCurSam}{iFirst + 1} ', using the Gibbs-SeaWater toolbox ' ...
'(TEOS-10) v3.06 from mean latitude and ' presComment '.'];
'(TEOS-10) v3.06 from mean latitude and ' presComment '.' tidalAmplitudeComment];
end
else
% without latitude information, we assume 1dbar ~= 1m
zOther = relPresOther;
computedDepthComment = ['depthPP: Depth inferred from only one neighbouring pressure sensor ' ...
descOtherSam{iCurSam}{iFirst + 1} ' with ' presComment ', assuming 1dbar ~= 1m.'];
descOtherSam{iCurSam}{iFirst + 1} ' with ' presComment ', assuming 1dbar ~= 1m.' tidalAmplitudeComment];
end
clear relPresOther;

Expand All @@ -653,7 +676,7 @@
zOther = interp1(tOther, zOther, tCur);
clear tOther tCur;

computedDepth = zOther + signOtherCurSensor*distOtherCurSensor;
computedDepth = siteDepth - nominalHeightCurSensor * (siteDepth - zOther) / nominalHeightOther;
clear zOther;
elseif iSecond ~= 0 && iFirst ~= 0
presIdxFirst = getVar(sample_data{nearestInsts{iCurSam}(iFirst)}.variables, 'PRES');
Expand Down Expand Up @@ -790,9 +813,9 @@
end
else
fprintf('%s\n', ['Warning : ' sample_data{iCurSam}.toolbox_input_file ...
' please document either instrument_nominal_height or instrument_nominal_depth ' ...
' please document site_nominal_depth or site_depth_at_deployment and either instrument_nominal_height or instrument_nominal_depth ' ...
'global attributes so that an actual depth can be ' ...
'computed from other pressure sensors in the mooring']);
'computed from 1 or 2 other pressure sensors in the mooring']);
continue;
end

Expand Down

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