Bluest of blue sky

End of June and we had an absolutely stunning day at Wytham. Mike and Zack from Skycap came up with their DJI Inspire and filmed the standing oak for the BBC documentary; we got some lovely footage around the tree which we'll see in the finished piece. Then we flew up from the site where Olli and Teemu from the Finnish Geospatial Institute (FGI) of the Finnish National Land Survey (NLS) have been based the last few days with their very impressive custom-built hexacopter. They have a multispectral imaging camera, with a gimballed cosine head downwelling irradiance sensor (for those who want to know!) which allows them to capture quantitative measurements of reflectance, not just pretty pictures. The first look at the Skycap footage is pretty stunning.

30 C and blue as the sea - the sky is always like this in the English summer - in my mind at least. I was very impressed with how steady the camera gimball kept the view regardless of the drone attitude. You can see the flux tower from around 0:20 s in, towards the top centre of the wood. The aim is to try out height model software, compare with the NLS data, and the Riegl canopy height model data.

Wytham Woods, summer 2015

We've been working in Wytham Woods, just outside Oxford, over the past few weeks, scanning and characterising the forest structure in a 6 ha (300 m x 200 m) area. This is the the largest single area we've scanned so far - quite an ambitious task, and is part of our work on the EU-funded METEOC-II project. 

Although the forest is not as dense or tall as the tropical forests we've encountered in Gabon, Brazil and elsewhere, it's still a challenge. Kim has been leading the team (Niall, Ally et al. from NPL, along with Toby and others from Yadvinder's group at Oxford) in setting up the plot, marking out the 176 (!) separate 20 x 20 m grid points, laying out targets and then doing the 352 resulting scans.

Following the lidar scanning, we're collecting LAI and hemiphoto measurements at all the grid points in the plot. The aim is then to be able to use the lidar data to generate a detailed 3D model of the whole site - something that's never been done before on this sort of scale - both leaf on, and leaf off. We'll then be using the model to simulate satellite observations, as well as ground-based observations (hemiphotos, LAI, fAPAR etc) with the aim of being able to provide traceable uncertainty from ground mesrements through to satellite observations. This is essentially impossible to do in 'real life' because you never know what the real LAI or fAPAR of a site like this is. So we're using the 3D model to simulate this process.

A rather lovely view from under the canopy in Wytham, showing the rather beautiful sun-dappled understory.

The woods at Wytham really are a lovely place to work, and very convenient. We're able to visit quickly, and there's a lot of other work going on with various groups, meaning there's good infrastructure. And good pubs and coffee within a 10 minute drive - essential, particularly if you're working there for several weeks at a time.

The Finnish Geodetic Institute UAV coming in to land.

Meanwhile, our colleagues from Finland have been deploying their UAV, with a gimbal-mounted hyperspectral camera on board, to collect spectral data from above the 6 ha site. This will tell us about what's going on in the upper part of the canopy. They have a very nice set-up on the UAV, with a cosine-weighted irradiance sensor (also gimbal-mounted) and some portable calibration targets on the ground. An impressive bit of kit. The video shows it coming in to land.

The FGI UAV. Note the irradiance sensor on the very top with the white housing.

The last of the 352 scans. Kim is happy.

Kim, Ally and Niall (L to R) try and get to grips with the rather primitive menu on the LAI2000. It's not iOS, for sure.

Lidar workshop in João Pessoa, Brazil

I've spent the past few days in João Pessao on the very Eastern tip of Brazil - the city where the sun rises first! I can certainly confirm that the sunrises are pretty spectacular - swimming off the beach from my hotel at dawn is pretty special, particularly looking back at the weirdly retro/futurist James Bond villain hotel.

Seeing the sun first in all the Americas!

The Hotel Tropical Tambau, with missile silo, shark tank and concrete nuclear bunker.

I was invited as part of the XVIIth Brazilian Symposium on Remote Sensing (XVII SBSR), a biennial science meeting for Brazilian agencies and specialists in remote sensing. The Brazilian government has invested heavily in remote sensing infrastructure and training for environmental monitoring over the last two decades, particularly in an effort to monitor and control deforestation and degradation, but more widely to support mapping, commercial and conservation activities. I was invited by Dr. Veraldo Liesenberg, a lidar expert from the Department of Forest Engineering (DEF), Santa Catarina State University (UDESC), to come and help lead a workshop in lidar remote sensing for forest mapping and monitoring, in conjunction with Dr. Akira Kato from the School of Horticulture, Chiba University, Japan. The workshop was run over the weekend prior to the main meeting (along side a range of other courses) and was aimed at showcasing the utility of lidar, both TLS and ALS, and in combination with image and other data, for addressing forest science. 

The meeting was held at the very new and shiny "Centro de Congresso de João Pessoa" of João Pessoa city, Brazil. The local authority have built the centre to attract large conferences o the region.

The workshop seemed to go down well and we had around 20 attendees who were mostly students, but also some postdocs, in Brazilian universities, all interested in what lidar could do for them. We presented new results from our work in ALS and TLS, and then ran a series of practicals looking at lidar data and some of the free tools that can be used to handle them, including Cloud Compare, Fusion, WEB-lidar, libLAS and so on. It was definitely an interesting meeting and I met a number of people with interests in our TLS work, and who potentially have plots and data that would be mutually beneficial. 

Everyone wants UAVs. And lidar.

There was also a large commercial expo as part of the conference, showcasing some very interesting new developments in UAV and ground-based tech. UAVs appear to be particularly attractive here due to the relatively lower cost of entry than many other, piloted systems. And the instrumentation and software is obviously advancing rapidly to allow exploitation of these platforms. 

New ESA Massive Open Online Course (MOOC)

The new ESA Massive Open Online Course (MOOC) I've been involved with has now gone live. The MOOC is a free, 5 session course of 2-3 hours a wekk, providing an introduction to monitoring of climate with satellites. It's aimed at policy makers, students, and anyone with a general interest in climate and so it's not technical. I was involved as one of the presenters, but don't let that put you off - some of the other bits are excellent. Please circulate to anyone you think might be interested. There's some really interesting bits on the solid earth, fires, the cryosphere, oceans, atmosphere and then other services which depend on EO data.


The course information page is here https://www.futurelearn.com/courses/climate-from-space and you can see some clips from our trip to the Amazon in the trailer below (e.g. at 2:19 - 2:30).

TLS demo for students and a nice view of the UCL quad

We took the TLS instrument out into the quad here at UCL yesterday, to demonstrate the capabilities of the instrument for collecting 3D data, and what you need to do in order to process those data into something useful. Thanks to Andy and Kim who set up the demo - you can recognise various people in the scan if you know them! They cast long shadows in the UCL quad (literally, rather than metaphorically, although ......).

Euronews!

The Reuters piece has been slightly extended and re-edited with some different material from me, and some additional animations (not from me) resulting in the following:
http://www.euronews.com/2015/01/26/laser-scanning-trees/
The piece makes a few different points, mainly about the methods, but also discusses the Brazil work a little more.

Short Reuters interview

The short interview I did for Reuters Technology is up. It showcases the recent Australia work in Kim's MEE paper but also the initial flythrough from Caixuana.


http://www.reuters.com/video/2015/01/14/3d-laser-mapping-weighs-trees?videoId=361763887&videoChannel=6&channelName=Technology