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Just a quick note: The panoramic photos for 2010 are now online.

Earthquake!

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A couple of days ago we witnessed a series of pyroclastic flows, and this morning it was an earthquake. I was out on the deck of the cabins. The cabins are on stilts but stand firm against the worst wind and rain that Costa Rica can throw at them. However, the structure had what could be described as an unnatural quiver - almost as if the wind had caught it in an unusual way. Except there was no wind.

Others felt it and after breakfast I checked online. The USGS are recording a Mag.4.8 earthquake at 9.894N  85.272W 46.7km deep, "Coast of Costa Rica" (actually locating it just on the Nicoya Peninsula). OVSICORI are giving it a slightly higher energy of 5.1. The differences are probably due to different equipment locations. Also the USGS calculation will be fully automated and as it is only a moderate non-US earthquake, it probably hasn't been examined by a human.

The coastal location means it is NOT an Arenal earthquake but an earthquake related to subduction of the Pacific Plate under the Caribbean plate. The depth is consistent with this - it is too deep for a volcano, and most earthquakes of this depth are related to subduction.

Here's the seismogram recorded by the OVSICORI Volcan Arenal seismometer (VACR):

VACR_seismogram_eq.png

The earthquake is the largest squiggle just after 6:45am local time. The seismometer even goes off scale.  It is only a moderate sized earthquake but we are fairly close, and the seismometer is set to detect vertical motions (the dominant kind in a thrust fault - which is the most likely for a subduction zone).

2010 Map Updated

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I've updated the new 2010 map to include the new buildings, the HOBO temperature sensor points, and the changes to the bird points.

The bird nest data has yet to be collected - I will update this map when we get the data.

Yes we had a lot of rain yesterday, but I managed to take most of the panoramic photos, and helped with the HOBO placement. I will be adding the HOBO locations to the map soon.

Today is much better and the weather is now clearing quite nicely - in time for the planned trip to Arenal after breakfast.

I have split the maps up into 2008-9 and 2010 due to the various changes. At the moment the 2010 map is identical to the earlier map but I shall be modifying it over the next day or so.

I have also enabled anonymous comments on the blog, so people "back home" should be able to comment. Previously you had to sign up but this wasn't working properly.
The anonymous comments will eventually attract spam so I will switch it off a few weeks after we return.

Well, we've just about finished our first. Very much an introduction day with the students getting their bearings and learning their birds and trees. A lot of progress has been made though.

I've created my first trial panoramic photo, and it worked first time - having a decent tripod makes a big difference.

There have been a few changes to the property. As well as the restaurant, there are a number of new cabins. A new path has been added below the original three cabins, and the turnaround area (Bird Point A) now contains a very young (but quickly growing) hibiscus maze. I've captured these changes with the Trimble and I will be adding them to the map in the next few days. I will probably create a new map for each new year starting with 2010. This time we do not have the insect points, but we've added two bird points and moved two bird points.

As expected, the trees have grown a lot since last year - so much that they are beginning to affect the Trimble (GPS) performance as they start to block out a lot of the sky. I won't be digitizing the new path because it is entirely in the mixed forest below the cabins.

Finally, here's an unusual looking white frog that Chris found near the cabins:


white_frog.jpg

new version of the map

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Yesterday I linked in a new version of the online map that uses Google Maps. This is similar to the other maps, but uses Google's new experimental "v3" map interface instead of Bing Maps or OpenLayers/MapServer. Although this means it has a couple of bugs (icons are too big, and it eventually crashes an iPad), it does support multi-touch interfaces, as used by the iPad and the new generation of tablet PCs.

PhotoSynths are online

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I've created the PhotoSynths and put them online at the new PhotoSynth page. PhotoSynth is a Microsoft product which htye have recently released from their R&D labs. It allows you to create a pseudo-3d image of an object or space using lots of photographs. The photographs are matched up, allowing you to navigate around the object or space. Some liken it to Google's StreetView product.

Due to the long time taken to process and upload the PhotoSynths, I had to store the images and process them back here in Texas.  Therefore it wasn't possible to correct any potential problems. Overally they can be described as "fair". They could be better, but some bits work very well.

There are two PhotoSynths. The first covers the area around the cabins, concentrating on the path connecting the three cabins, but also including the steps up to the 'Monkey Cabin'. It includes a number of 360 degree views.

The second PhotoSynth attempts to give a walk along the 'Bird Path', starting at the turnaround (below the cabins) and finishing at the bottom of the slope below the stables. Some parts of this work well, but PhotoSynth had problems connecting some sequences to each other, and with the darker areas. It is recommended that you view this PhotoSynth in "slide show mode".

Final Field Day

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Well, we've just about finished the last day. For scheduling reasons we swapped Field Day 5 with the free day, so yesterday the group spent their field day with a boat trip along Cano Negro. The students are posting their comments, but this year we saw quite a few good views of unusual birds, Caimens, and all three types of monkey (howler, white faced, spider). This was followed with an hour in La Fortuna, and some time at the reserve that Giovanni is managing.

Here is a photo of the students on the boat trip (from left: Nick, Aliza, Kathryn, Natalia):

group_boat_photo.jpg

Today, the final field day, has been a day of tidying things up. We retrieved the last HOBOs (automated water temperature samplers), and both Aliza and Nick have been collecting their last field data. I've also converted the Trimble data into a form that can be used by Aliza and Nick in their write-ups. I've created a new map with bird nest locations. The plan is to add bird nest locations each year as their own layers, so it should be possible to compare the number of bird nests over time. Marcy reports that there are a lot more bird nests this year than in the 2008 field season. This is good news. An intermediate version of the map should be online before we leave Leaves and Lizards. Aliza is preparing a set of photographs for each bird nest point. I shall publish these later in the week after we return. I'll post a note when these are completed.

We re-shot two of the panoramas this morning, and I've been working on data processing. Although there hasn't been any careful alignment with 2008's photos yet, we have two of of the 2009 panoramic photos up:

(the new panoramic photo view requires the Silverlight 2 plugin installing)

As you can see, the growth around Bird Point C is quite amazing. Look at the teak saplings in the distance, and the cabins (in 2008).

I should have all of the panoramic photos processed by tomorrow, and then I'll start aligning them. First impressions are that alignment is not as critical as I was fearing. (I am also starting to experiment with PhotoSynth - more news when I have something to show)

In other news, this has been quite an adventurous day but everyone else has covered that. The main message is that parents should not be worried!

(oh and there was a small explosion, well really a burp, from Arenal - unusual in that I was actually watching and saw it before the sound reached us)
Mainly technical news from me today. This morning, Microsoft added a "Content Delivery Network" to their Virtual Earth maps. I've already updated the EcoMap Costa Rica maps to use this. The changes aren't noticeable here in Texas, but should be quicker for other parts of the world (Microsoft claim up to 80% faster).  Of course we have been using our own "Content Delivery Network" since April for the ASTER satellite image and the aerial photograph, so Microsoft are a bit slow in this department!!    (we are using Amazon's CloudFront service for these aerial photos, and the larger downloads such as student reports and the panoramic photos)

I've dusted off the camera attachments to take the panoramic photos. We will use the same procedure as before: Taking 16 photographs at 30deg intervals using a Panosaurus panoramic head, and a Canon EOS with 20mm lens.

This year we have the comparison tool (which I see Katheryn mentioned yesterday) that allows us to fade from one image to another. A big problem is going to be image alignment. Last year's images were marked with the "North" direction, so lateral alignment should be straightforward. Vertical (azimuth) alignment will be more difficult. Also we are going to have to be careful to choose the exact same spots. We have the coordinates (good to 6m), our memories, and printouts of last year's photos.

For the photography, I am also going to try Microsoft PhotoSynth. This is a sort of pseudo 3d photo technology. Here is an example of our back yard. It takes a bit of practice, and the back yard example could be done better. We may have a lot of trouble with the forest. PhotoSynth does not work well with lots of similar objects - so teak plantations are probably not going to work. I also suspect loreals are going to give trouble. However we could try creating a PhotoSynth for specific areas such as around the cabins, or around the main house. The limited back yard example took over 100 photos. Are there any snap-happy students who would like to help?

The new implementation of the Virtual Earth map that uses the MapCruncher-produced satellite image and aerial photograph, is now the default map:

http://www.ecomapcostarica.com/map/index.shtml

The original MapServer/OpenLayers map continues to be available here:

http://www.ecomapcostarica.com/map/index_ol.shtml

None of the commercial map systems have sufficient coverage of the Leaves & Lizards property, so in 2008 I had to implement our own maps using MapServer and OpenLayers. In the past year it has become practical to create our own satellite tile layer using Microsoft MapCruncher. This has made a usable Virtual Earth map a practical proposition. Debbie at Leaves & Lizards supplied the aerial photograph which has also been included in the new Virtual Earth map.

9 days and we shall be at Leaves & Lizards for the 2009 field season...

The panoramic images are now displayed using a new comparison viewer. This allows you to view panoramic photographs taken at the same location but from different years. A slider fades the view from one image to the other image.

Note: As the 2009 images have not yet been taken these appear black. When using the viewer, you will need to move the slider from 2009 to 2008. This will fix itself as we create the new 2009 images next month.

Also, last week I added a new aerial photograph to the Virtual Earth version of the maps. As with the ASTER image on the same map, this was converted into map form using Microsoft's MapCruncher program. It was tied to the real world using GPS coordinates taken during the 2008 field season. The aerial photograph is much higher resolution than the ASTER image. It was taken after the cabins were built but before the first plantations were planted.

Yesterday I published an article at GeoWebGuru about how the ASTER satellite image was added to Virtual Earth using Microsoft MapCruncher and Amazon S3 & Cloudfront:

Add your own Satellite Images to Virtual Earth with MapCruncher and Amazon S3

A new version of the Virtual Earth map is now online:

http://www.ecomapcostarica.com/map/index_ve.shtml

(Click on the map image to reach the main map application)

This version is a completely native Virtual Earth application and does not use OpenLayers or MapServer WMS. The map is now full-window sized, without the header and side bars. You can zoom in much more than the original version, and it also now supports the Virtual Earth 3D control!  Yes you can fly around a reasonably high resolution 3d Volcan Arenal, or soar along the Leaves & Lizards ridge.

The above map will probably become the main map in the next few weeks.

The satellite image was tiled using Microsoft's MapCruncher, and the tiles are stored on Amazon S3 servers and distributed using CloudFront. I shall be publishing a how-to article at GeoWebGuru about this on Monday.

Legend added to the maps

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I have just added a legend to the maps. Although I might adjust the maps further, they are now complete.

I have also adjusted some parameters for the MapServer layers (base map, satellite image, synthetic streams) to make them load more quickly. The improvement should be more noticeable on slower internet connections.

MP2KMag.com have just published a 'how the sausage is made' article that I've written:

Using Virtual Earth with OpenLayers

This article concentrates on the Virtual Earth version of our maps, showing how you can use OpenLayers with Virtual Earth. The article example uses OpenLayers to add a SHP shape file layer (served by MapServer using WMS) onto the Virtual Earth base layer.

Our production maps also use OpenLayers to draw the survey grid, and to add KML layers.

The 'Website Technology' page is up. This is an initial page and lists the technologies and data sources that we have used for the site. It will be expanded over the next few weeks to give more information. It may be expanded into multiple pages if I decide to give a more in-depth discussion of specific areas. The page is here:

http://www.ecomapcostarica.com/ref/website.shtml

The descriptions for the website and this blog are only included for completeness. The panoramic photographs and online maps are more interesting.

Yes a new version of the map but with a Virtual Earth base map is now online.

Virtual Earth gives much better coverage for wider Costa Rica and Central America, but does not work as well when zoomed in (ie. to the Leaves and Lizards property).