Friday, April 20, 2012

Is the sea ever actually level? The lesson of Bikeman, Kiribati

Ever wonder what's really happening to the low-lying islands in the tropics?

My former student Cory Kleinschmidt and I made this video about complicated geological and social dynamics at play in loss of Bikeman, an islet in the lagoon of Tarawa Atoll, the capital of Kiribati. The science behind this story and others in the ongoing "Battle of Tarawa" is described my feature in the latest issue of EOS, Transactions of the American Geophysical Union.

I'm heading to Kiribati to do some climate and coral reef monitoring with colleagues in the local government. I'll try to post about our work periodically, provided the internet cooperates, and our boat doesn't sink.


Monday, April 16, 2012

Climate experience makes some corals more resistant to heat stress

Preserving coral reefs, and everything they provide to communities across the tropics, on a warming planet will require identifying what might make a coral less susceptible to heat stress.

One of the big questions being studied by a number of scientists in the community is whether past temperature experience can make individual corals (by individual acclimation or adaptation) or coral communities (by selecting for tougher species) more resistant or more resilient to heat stress. I've been leading field projects in the Gilbert Islands of Kiribati, where this whimsical coral can be found, because the unique El Nino-driven climate provides a great natural laboratory for studying that big question.

In the lastest publication on this research, my colleagues Jessica Carilli (the lead author), Aaron Hartmann and I describe how massive corals on the atolls which naturally experience more frequent heat stress appear to have been more resistant to the recent El Nino-driven ocean heat waves. For an accessible summary of our findings, I recommend listening to this past weekend's episode of CBC Radio's Quirks and Quarks. But you can also read the paper itself: the journal PLoS-One is online and open access to all.

The research involved drilling coral cores, Jess Carilli's area of expertise, from sites around three different atolls, followed by some exhaustive lab analysis by my colleagues. The logistics of collecting the samples from the outer islands was unbelievably complicated, even for someone who knows the challenges of working in a remote island country. Just getting all the gear to Butaritari (that's the seat beside my flip-seat on the plane), making it all work and bringing the samples back intact will probably go down as our greatest accomplishment in science. We owe a huge thanks to local colleagues Aranteiti Tekiau, Toaea Beiateuea, Iobi Arabua and the late Moiwa Erutarem, who sadly was lost at sea six months after our expedition.

In the month of May, I'll be fundraising for the in-country expenses of a planned, future expedition through the second Scifund crowd-sourcing science funding campaign. By sheer coincidence I will actually be in Kiribati during some coral monitoring during most of the Scifund campaign. I'll try to put trip updates on Maribo whenever I find internet access.


Friday, April 13, 2012

Mountain pine beetle upends the Canadian emissions picture?

The lastest Canadian greenhouse gas emissions data looks very different if Canadian forests are taking into consideration.

There was some rejoicing over the fact that Canada's GHG emissions grew by only 2 Mt CO2e (that includes CO2 plus other GHGs converted to "units" of CO2) or 0.25% from 2009 to 2010, despite the fact that the economy was rebounding from the recession. But if you include land cover, land use change and forestry, GHG emissions grew by 86 Mt from 2009 to 2010.

Why such a large change? According to the Canadian government model, forests went from a net sink of 17 Mt in 2009 to a net source of 72 Mt in 2010 (see Table 7-1 in NIR). If you

break the GHG balance of forests up by region, the driver of this change was the "Montane Cordillera", or #14 on the map to the left. These forests of western BC were a net source of 100 Mt. The only other net sources regions in 2010 were the "Boreal Shield West" (#9 at 22 Mt), the "Pacific Maritime" (#15 at 5.7 Mt) and the "Taiga Shield East" (#4 at 1.7 Mt).

There are large, natural year-to-year variations in forest carbon balance, so it's important not to read too much into the jump from 2009 to 2010. What the 2010 number does reflect, however, is the very large amount of carbon, in the form of dead wood, in BC that is waiting to be respired to the atmosphere (if we don't use sequester it in buildings). For that, we can largely thank the Mountain Pine Beetle, the outbreaks of which have been linked to climate change. From the National Inventory Report:

The upward trend in dead organic matter (DOM) decay since the year 2000 reflects the long-term, growing effect of past disturbances, especially insect epidemics that have left substantial quantities of decaying DOM. Over the last decade, insect epidemics have affected a total of over 56 Mha3 of managed forests, with 72% being located in the Montane Cordillera reporting zone and corresponding to the epidemics of Mountain Pine Beetle. In contrast, much of the interannual variability of the GHG budget of managed forests hinges on the occurrence and severity of fires.

Before you start screaming "cover-up", it is standard UN reporting practice, to not include land use, land cover and forestry in the "total" at the top of the GHG inventory tables. This is done for a number of legitimate reasons, not the least of which being that net emissions from forests must be estimated by models and, as I've said, the results vary from year to year because of climate variability. Nonetheless, it is striking that climate change, via its effects on Canadian forest, might be undoing the reported progress in curbing, or starting to curb is a better term, greenhouse gas emissions from some sectors of the Canadian economy.


Thursday, April 12, 2012

Canadian GHG emissions in perspective

The Canadian government submitted the latest national Greenhouse Gas inventory report to the UN yesterday, which features data through the end of 2010. As was highlighted in the Environment Canada press release and the media, GHG emissions grew by only 2 Mt CO2e (that includes CO2 plus other GHGs converted to "units" of CO2) despite the fact that the economy was rebounding from the recession. This was viewed by some, including the Environment Minister, as good climate news, because it suggests that  the economy is decoupling from greenhouse gas emissions.

For some perspective, here's a plot of Canada's GHG emissions since 1990, together with various policy targets (Kyoto, Canada's own 2020 target, the EU reduction target for 2020) and emissions projections (Energy Information Administration's 2020 projection for Canada). It was quickly adapted from a recent presentation. The "decoupling", if real, which is questionable given that Canada's economy is shifting more towards resource-intensive industries, has to seriously accelerate even to hit Canada's much-criticized 2020 goal.

There's an important and very telling missing nugget in the emissions total. I'll get to that tomorrow.
NOTE: The lines look "steeper" because the y-axis on the chart begins at 400 Mt; the Canadian government report uses a y-axis from 0 - 800 Mt.