Back |
Explanation to the Google Earth images and data
|
Galathea right now
|
Galathea-3
Follow the ship in Google Earth
The ship is reproduced in
scale (1:1)
in Google Earth using Google
SketchUp
Loaction data
delivered
by DIFRES |
Cruise
track with data
|
Galathea-3
Route
with data direkt from
the ship
You can see the data by
clicking on a time marker on the track
Time is given as UTC (Universal time)
You can also download the complete datafiles
directly
DATA
Data delivered
by DIFRES |
|
Route as planned
before departure.
Markers indicate approximate target position at 10:00 UTC of the day.
The route will be continously adapted according to the needs of the
scientific projects.
|
Galathea 3 in Copenhagen
|
Galathea-3 in København
Aerial photograph in Google Earth
Galathea-3
in the harbour of Copenhagen before departure Friday August 11, 2006.
Aerial Photograph by
|
Algae
|
Phytoplankton
Maps
The algae or
phytoplankton maps are based on Level 2 data from the MERIS-ENVISAT
instrument. The Level 2 standard MERIS data products encompass
radiance measured at each spectral band (band 1-14). These radiances
are transferred into the so-called water-leaving reflectance after
careful correction for atmospheric influence and disturbance.
Additionally the standard products contain calculated maps of water
constituents. The algae map is the most significant of these, and it
is expressed with units of chlorophyll pigment in mg/m3.
In the images, cloud and land areas are masked using threshold
algorithms. A complicated bio-physical model and algorithms complex
is needed in order to calculated the algae concentration. And since
the signal from the water is quite low, some error has to be expected
in the final product, typically +/- 30%, but more along cloud edges
and along coasts. The resolution (each pixel) in the images is 1 x 1
km.
|
Sea Surface Temperature
|
High
Resolution SST
The
gridded SST products are based upon satellite observations from several
instruments (AATSR, AVHRR, AMSR, TMI, MODIS and SEVIRI). These include both
infrared and microwave observations. As the
infrared
observations are limited by cloud cover and the microwave
observations are rather coarse, an objective analysis method has
been used to blend the data in an optimal way to produce a high
resolution SST product. The method uses statistics to fill out the gaps
and calculates a SST field every day with a
resolution
of approximately 5 km in latitude and longitude.
The
error on the SST will vary from below 0.3 degrees in cloudfree areas to
about 0.7 degrees in regions with clouds and very variable
conditions. For animations, see: http://ocean.dmi.dk/satellite
In addition, a more coarse resolution global microwave image from
Remote Sensing Systems in
Californien is shown.
|
Global Ozone
|
OZONE
The observations of total Ozone is presented in Dobson units and is
based upon the measurements from the Ozone Monitoring Instrument (OMI)
on the EOS AURA mission
(http://aura.gsfc.nasa.gov/instruments/omi/index.html).
The observations are performed during daylight where OMI provides daily
global coverage. The absolute accuracy of the product is 3%.
According to NASA, an ozone hole is defined as an area where the
total ozone is below 220 Dobson units. The resolution of the
global grid is 1.25 degrees in longitude and 1.0 degree in latitude
|
Sea Ice
|
Sea ice
Opdated several times per day
From NASA microwave radiometer data
Produced by DTU
See also http://www.seaice.dk
.
|
Wave heights
|
Wave heightsr
--------------------------------------------------------------------------------------------------------
|
Bathymetry
|
Bathymetri - Depth of the
ocean
Stationary - is not updated
Not measured by satellite
Leveret af National Geophysical Data Center, US
|
SSH anomaly
|
SSH
(Sea Surface Height) anomaly
The figures are based upon near real-time observation of sea
surface height from the altimetry satellites: ENVISAT, Jason-1 and
Geosat Follow-On. The observations are anomalies, which means that the
mean
sea surface has been subtracted before gridding. In addition, the
different
satellite products have been adjusted to each other. The
error on the individual satellite observations is about 5 centimeters.
These observations from the individual tracks are subsequently gridded
onto a global grid with a resolution of 0.25 degrees in longitude and
latitude. A new grid is produced every day and is based upon
observations from a week, with the newest observations being a few days
old.
For more information on the product, see: http://www.aviso.oceanobs.com/
|
Wind
|
Ocean winds
<>Ocean wind maps are mapped from two
satellites: QuikSCAT and Envisat. <>Onboard QuikSCAT is a
scatterometer
that observes ocean wind speed and wind direction, i.e. the wind
vector. Any location on Earth is observed (minimum) twice per day
with a spatial resolution of 25 km. QuikSCAT global wind maps are
obtained from NOAA http://manati.orbit.nesdis.noaa.gov/quikscat/.
<>
Onboard Envisat is an Advanced
Synthetic Aperture Radar (ASAR). The normalized radar cross section
data observed are translated to ocean wind maps at Risoe National
Laboratory (link http://www.risoe.dk/galathea/opslag/satellitbilleder.htm)
using the Johns Hopkins University, Applied Physics Laboratory
software. The spatial resolution in the wind maps is 600 m. Each wind
map covers a selected region near Galathea-3.
For arkivbilleder: http://galathea.oersted.dtu.dk/google/kmz/images/Wind/
|
Globalt cloud cover
|
Globalt cloud cover
Updated 4-8 times per day.
From Geostationary satellites around the Earth. Data from polar regions
are unreliable. .
From University of Bremen.. |
MERIS
|
Visible image of
mostly clouds.
Produced by ESA
This link goes to the latest relevant image available.
For archive images see: http://galathea.oersted.dtu.dk/google/kmz/images/Vejr/
|
Wave Heights
|
SWH
The figures are based upon near real-time observation of significant
wave
height (SWH) from the altimetry satellites: ENVISAT, Jason-1 and
Geosat Follow-On.
Significant wave height is defined as the average of the highest 1/3
of the waves. The satellite observes the SWH directly beneath the
satellite in a circle with a diameter with approximately 5 km.
The observations from the individual tracks are subsequently gridded
onto a global grid with a resolution of 1 degree in laitude and
longitude.
The error on the satellite observations is about 0.2-0.3 meters. A new
grid is produced every day and is based upon observations from a week,
with the newest observations being a few days old.
For more information on the product, see: http://www.aviso.oceanobs.com/
The resolution of the grid is 1 degree in longitude and latitude.
|
Radar image (ASAR)
|
Latest relevant
radar images from ESA's ENVISAT satellite
ENVISAT's Radar (ASAR) records images of up to 450
kilometer swath width as it orbits the Earth (WSM).
Higher resolution of narrower swaths asa also sometimes available (IMM).
This link goes to the latest relevant image
available.
For archive images see: http://galathea.oersted.dtu.dk/google/kmz/images/Radar/
|