All Things Sustainable

ecology, economy, community


Of Ice and Oceans (climate again!)

This week at the Exeter MOOC that looks at ‘Climate Change’ and its complexity we first looked at the impact of global warming on ice sheets, glaciers and sea ice. Understanding how the warming earth disturbs, amplifies or changes the natural processes of glacier calving and ice sheet melting is really critical. We are depending on this when we estimate how fast and how high sea levels will rise in the coming years. If all the ice sheets melt the sea rise would be 65m but of course that will take quite a long time. Even so with many people living at elevations little more the a meter or two above sea level things will get a bit uncomfortable. Understanding how the glaciers behave will also be critical for understanding the fresh water cycles I think, countries in Asia with high populations and huge rivers may well be put under threat because many of the Asian rivers are fed by Himalayan glacial meltwater. We were given web addresses that showed photographic evidence of a massive decrease in the size of the Himalayan glaciers. There were panoramic photographs taken by the British in the 1920s and again in recent years the glaciers have been photographed from the same positions. Side by side (or actually one above the other) they make a sobering comment on the future.
Glacierworks:Everest is definitely worth exploring.
http://explore.glacierworks.org/en#glaciers

Well that was the first half of the week and the second half was just as challenging because we now started to look at the effects of CO2 being absorbed into the ocean. This is quite a complex thing to get your head around as well.
It involves a bit of chemistry but not too much because I could follow most of it (I think) and chemistry was never my strong point. It works like this … the CO2 dissolves in the sea water and forms a weak acid which then dissociates into free H (hydrogen) ions and carbonates. The carbonates would normally be available to be combined with calcium and used to form the shells of the tiny sea creatures at the bottom of the food chain, but if the environment is made more acidic by an excessive amount of free hydrogen ions the process starts to fail. The acidity in the ocean starts to damage the shells of the tiny phytoplankton and pteropods that form the basis of the ocean food chain and it also makes it much harder for their shells to form. I think of this as being similar to plant sensitivity to soil ph, for example many vegetables can only access nutrients within a certain ph range and we can test our soils and adjust them if necessary. Pity we can’t do that with the ocean.
This ocean acidification is one big long term threat to the ocean food chain and all the people that depend on reefs, estuaries, lakes and inlets, fishing and aquaculture for much of their protein, sport and relaxation. We all need to worry.

Fishing in a lake near Bermagui

Fishing in a lake near Bermagui

I also followed up on some work I had come across by a paleo-climate scientist Andrew Glikson, Visiting Fellow at ANU School of Archeology and Anthropology. One thing I found was information on the relationship between the high levels of CO2, increased sea levels and the four large mass extinction events that have occurred in the history of the earth. It seems to me if rising CO2 on a geological timescale (taking aeons to build up) can cause mass extinctions then there is very little hope that the same will not happen with the current rate of CO2 increase in the atmosphere. We urgently need to stop producing the stuff as we power our homes. Old King Coal has got to go.
Andrew Glikson mentions something called “serpentine sequestration” but all I could find on that was a rather heavy paper from Bath Uni which talks of capturing CO2 and reusing some of it in high tech manufacturing of polymers etc. but the paper recognises that the big problems are cost and finding enough space to sequester the CO2 once it has been captured. It seems to be another attempt at using the mind set that created the problem to attempt to solve it.
On the other hand he also speaks of using soil carbon and a world wide effort to sequester carbon in forests and agricultural projects. And of course we must cut our emissions to Zero ASAP.

Advertisements


Climate change: models and fingerprints

This week the University of Exeter Future-Learn getting-bigger-all-the-time MOOC took a long hard look at models (no NOT Naomi Campbell) I am talking about massive super computer analysis of weather and climate and all that stuff. When the models are first constructed they are run using known historical data going back about 150 years and the climate outcomes they produce can then be verified against the historical records. This gives a level of confidence in projections plotted for future outcomes. This is also how the fingerprint of anthropogenic warming was identified because the models run from 1970 onwards will not match the climate records for that period if the CO2 that results from burning fossil fuels is excluded from the data set.

Modelling a future outcome
Of course we don’t know the future levels of CO2 or population or uptake of renewable energy so things like this become the variables and the model then indicates the likely result for any one particular set of circumstances. What can (or should) be articulated clearly is that the outcome for the future is firmly our hands and that increasing CO2 emissions must be curbed. It seems that we have already pumped enough CO2 into the atmosphere to make sure that sooner or later the temperature rise will equal or exceed 2degC and dangerous climate change will catch up with us.

Geoengineering
The next thing under discussion was the vexed subject of geoengineering and rather than try to précis such a complex issue I am including a youtube link – it lasts about 25mins and does cover a few other things as well. Things like clouds, did you know that those light whispy cirrus clouds that once were seen as heralding a fine day are villains in the climate scenario and likely to increase warming while threatening low clouds have a cooling influence? In someways it seems a bit back to front.
Carbon Capture and Storage, that old furphy is still being rolled out but high cost and the doubtful prospect of finding enough suitable storage seems likely to keep it as a pipe dream. Most of the “reflect the sunlight” schemes proposed would seem to have serious problems and while vegetation and trees are briefly mentioned there was no discussion about the storage potential of forests in general or old growth forests in particular. There was mention of increasing ocean storage potential but there are difficulties in making it effective. Check out the video below for more details.

Next week we will be looking at climate change impacts on the ice and the oceans. As previously there will be visiting specialists on hand to make everything clear. We certainly are getting the info straight from the horses mouth (for want of a better analogy)


1 Comment

A government of Vandals

In Sustainability, Society and You we have looked at business and the trust deficit. I can say for sure that this week has left me with a distinct trust deficit and not only in relationship to business. In response to their actions and announcements I now see my government as one that is determined to degrade any environmental or climate change action or legislation and is prepared to drive coal production as far and fast as it can. A government of vandals, they are trying to drag us all into a bleak future of 6deg temperatures.
I saw the approval of the proposal to allow Abbotts Point dredging spoil to be dumped on the Great Barrier Reef in order to facilitate coal exports to China and India, the Tasmanian forest classification about to be downgraded to facilitate the logging industry and seismic surveys about to be approved in waters south of Kangaroo Island that are home to many whales including the very rare Shepherds Beaked whale, in the interests of the oil industry.
Western Australia has started shooting sharks because they are the top ocean predator and sometimes they attack people who trespass on their territory. This is occurring in an ocean that is being continually disturbed by the actions of huge companies mining for oil and gas, so disruption to migration paths are likely and it is hardly surprising that normal behavior is changed.
Meanwhile the CSG industry tries to reassure us that the risk of contaminating ground water by pumping carcinogens underground is all in the best interest of the farmers and the whole population. And whatever you do don’t talk about climate change, even though Queensland farmers are still in drought and many may go under if the promised rain fails to materialise.
Government is elected to act in the best interest of the people. There is a certain cognitive dissonance here I think.