State of the Planet

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Back to Bangladesh, changing plans as we go

Bawali
The M/V Bawali, the boat we are using to go to Hiron Point in the Sundarbans mangrove forest

In Bangladesh we find that nothing ever goes according to plan, but we have always been able to accomplish our goals. So far on this trip, we have had to adjust from before we even got on the plane. The snowstorm on Feb. 13 cancelled Scott and his student Allan’s flights to New York from Wilmington, N.C. It looked like they would be delayed by a day, but then it worked out for them to drive to South Carolina to catch a flight. I was then able to pick them up on my way to take them to the airport for our flights to Bangladesh. There were seven of us going there together, but only six made it onto the plane. There were problems with his ticket, probably from the attempts to get to New York, and he couldn’t get it fixed in time to make the flight. Allan’s ticket was OK, though.

Chris Small and Kushal Roy of Khulna University making plans for fieldwork on the Bawali
Chris Small and Kushal Roy of Khulna University making plans for fieldwork on the Bawali

Not having Scott meant rearranging our plans. Plan B. We switched the order of things. Allan and I would go to Hiron Point in the Sundarbans mangrove forest first, since I could service the GPS there alone, but needed him for most of the other work. The silver lining was one of my equipment boxes didn’t arrive. It would not arrive until the next day when Scott could pick it up. I didn’t have to delay leaving Dhaka. After stopping by Dhaka University, I headed to Khulna to join Chris Small and others on the M/V Bawali. Chris was able to rearrange his work so we could sail to Hiron Point first. We got to the ship around 4 p.m. after a day of driving and a two-hour ferry ride across the Padma River, as the combined Ganges and Brahmaputra Rivers is known. We waited for Kushal and his students from Khulna University to arrive, then started the trip to Hiron Point near the coast.

A deer stands among the salt-filtering aerial roots of the mangrove trees in the Sundarban
A deer stands among the salt-filtering aerial roots of the mangrove trees in the Sundarban
The trim line of the leaves on the trees marks the height to which the deer can reach. Mud flats are exposed at low tide.
The trim line of the leaves on the trees marks the height to which the deer can reach. Mud flats are exposed at low tide.

We made good time and got to Hiron Point in the morning. We installed a GPS at the forest ranger station near a tide gauge.  The tide gauge measures the water level relative to land, a mixture of sea level rise and subsiding of the land. Our GPS measures just the subsidence of the land, accurate to 8 mm each day. The combination of rising sea level and sinking land puts Bangladesh at greater risk of inundation. Thus the sediment deposited by the rivers is critical for maintaining the land and the mangrove forest. So far, it looks like sediment is keeping pace in the natural environment, but there are problems where man has made changes. We installed the GPS in October 2012. While we put in communication equipment, the site is so remote that there was no cell phone signal to download the data. Hence, our visit to collect it manually.

Everything looked fine, but when I tried to connect to the GPS, I couldn’t. The set-up for the communication equipment meant the settings were different and locked. After a frustrating hour of attempts, including a hard boot to reset the system, I finally found the right settings to talk to the device. The trip wasn’t in vain. Downloading the data, I found something had gone wrong last July. We had good data until July 19, then one giant file with a date in 2025. I hope that it actually contains good data, but I won’t know until I get back and can get it to someone to look at it. Even better, my hard reboot cleared out the problem, and the GPS started recording data properly again. Even if we have a data gap, we will still be able to see the data trend for the subsidence rate. Taking two days to come down here was worthwhile.

We spotted an eagles nest as we sailed down the channel to Hiron Point.
We spotted an eagle’s nest as we sailed down the channel to Hiron Point.

The next problem was that the Bawali couldn’t get out of the small channel by the ranger station until the next high tide. We were stuck for eight hours. We used the time to explore the channels, but we would not be able to get to our next stop on schedule. Time for another change in plans. We are up to Plan C. We decided to go back so I could get off the boat and join Scott, who has hopefully arrived. We will do our on-land work and then rejoin the Bawali in a day and a half, if all goes according to plan. Not a sure bet on this trip.

Fishermen setting nets in a tidal channel near Hiron Point.
Fishermen setting nets in a tidal channel near Hiron Point.