Satellite Gremlins of Doom

The weirdest thing about doing a PhD is that everyone who isn’t in the academic game assumes you’re smart. I’m going to let you in on a little secret: smart people DON’T do PhDs.

Yes, this is me. No, it wasn't a good day.

Right now, I understand next to nothing about the subject I’m supposed to become an expert on. Within three years, I’m supposed to know more than anyone else in the world about The Conundrum of Weight Gain. It’s absolutely ludicrous (and more than a little terrifying)… But people do crazy things all the time, right?


My blog is a work in progress because it’s based on research in progress: if it doesn’t evolve then I’m not doing it right. Furthermore, I really shouldn’t be attempting to explain where satellites fit into my project just yet… but I feel I must say something in loving memory of MERIS. I know this doesn’t make any sense but that’s because I must first ambitiously wax lyrical about Ocean Colour!

Much of the information upon which ocean colour studies are based comes from satellites. Traditionally, from sensors called MERIS, MODIS and SeaWIFs. These aren’t the actual satellites, they’re the sensors on different satellite systems. MERIS is aboard the Envisat satellite, SeaWIFs is on the OrbView-2 spacecraft and MODIS is onboard Aqua. These satellites form part of larger Earth Observing Networks, and each sensor produces data products which help us monitor and measure the ‘green-ness’ of our oceans. I suggest reading “Where it’s at” for my relatively incoherent explanation of why this is important… or watch this short (but seriously annoying!) clip from the ESA website:

Highly productive waters inside an Antarctic polyna ( If only Marion waters looked this good!

Satellite accuracy goals generally accepted by international missions are only around 35% in the open ocean. Sensors do normally perform better than that, but this is totally dependent on the region in question. If you’re studying coastal regimes or high latitudes waters like the Southern Ocean, things can get complicated. And boy, do I have a thing for complicated…

Chlorophyll-a concentration: a measure of the 'green-ness' (

To notch up the drama, something incomprehensible happened to MERIS this week. The Envisat satellite simply stopped communicating with Earth on the 8th, and it has remained resolutely silent since. SeaWIFs already stopped talking in December 2010, so of the three sensors dedicated to measuring global ocean colour, only MODIS remains. And the replacement satellites, ESA’s Sentinels 1, 2 and 3 are only due for launch in 2013/2014!

MODIS ocean colour (

ESA’s mission control is frantically working to try and re-establish contact… but Envisat has already been in orbit twice as long as originally planned. That’s pretty impressive going. Despite being beyond the fall-out-the-sky-sell-by-date, MERIS’s data was GOOD and I was planning on basing a proportion of my PhD on it. No biggie. It’s not like I’m crying myself to sleep or anything…

Beloved Envisat with the MERIS sensor onboard (

For a superb explanation of Ocean Colour and what happened to MERIS (also: how to make the best poached eggs in the world), I highly recommend my dear friend and colleague’s blog:


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s