Climate Change, Acidification, & the Oceans, Conservation & Sustainable Management, Ocean Ecosystems

What the GBRMPA chair DID NOT say about my coral bleaching article

In April 2016 I submitted an article to The Marine Professional – a publication of the Institute of Marine Engineering, Science & Technology (IMarEST) focusing on the mass bleaching event that had hit the Great Barrier Reef at the time.  In their September 2016 issue, The Marine Professional featured a comment from a reader, in which he stated that he shared the article with Dr. Russell Reichelt – chair of the Great Barrier Reef Marine Park Authority.  The reader alleged that  Dr Reichlet told him that the article “contains some accurate things mixed with half truths and alarmism”.

A number of  coral reef, marine biology, and climate scientists have been in touch to express their concern about Dr Reichelt’s alleged comments on my article.  After liaising with Dr Reichelt’s office*, I am pleased to be able to set the record straight on what he did – or rather did not say.

*I did contact Dr Reichelt directly, but he replied via his office not directly.

After corresponding with Dr Reichelt’s office to determine where the “half truths and alarmism” were in the article, I have been informed that, whilst Dr Reichelt recalls the article being brought to his attention, he never made any such comments about the article.  In fact, he hadn’t even seen the article to comment on in the first place.  He has since read the piece and agrees that it is factual.

I have not attempted to contact the reader to find outwhere his comment came from.

Below is a copy of the article I submitted to The Marine Professional.   For those who want to see the article after it has been through their editorial process, please see the June 2016 edition of The Marine Professional.

Continue reading “What the GBRMPA chair DID NOT say about my coral bleaching article”

Climate Change, Acidification, & the Oceans, Fisheries, Aquaculture, & Sustainable Seafood

Climate Change Impacts on Kenya’s Fishery-dependent communities

 We now have a number of scientific studies that tell us how climate change is altering coral reef ecosystems, but how will these changes impact on communities that depend on them for their livelihood?  According to Joshua Cinner of James Cook University in Australia and colleagues from around the world, that answer depends more on the  community capacity for adaptation than its location.

Fishery-dependent communities in Kenya are not in a great situation.  Their reefs were heavily affected by a massive bleaching event in 1998 that has been linked to an extreme El Niño event and have not necessarily recovered as well as we might hope, and Kenyan reefs are likely to face increasing amounts of climate-related stress into the future.  Across three years, Cinner and co surveyed 15 ecological sites associated with 10 coastal communities along the Kenyan coast.  Using a range of ecological indicators of vulnerability of these reefs, they linked up the ‘health’ of the ecosystems with the vulnerability of the human communities that depend on them. Continue reading “Climate Change Impacts on Kenya’s Fishery-dependent communities”

Climate Change, Acidification, & the Oceans, Conservation & Sustainable Management, Fisheries, Aquaculture, & Sustainable Seafood, Marine Life

Oceans on Acid

As we continue to burn fossil fuels, produce cement, and alter land – like clearing forests that would normally convert atmospheric carbon dioxide (CO2) into oxygen, the levels of carbon dioxide in the atmosphere continue to increase.  Between 1995 and 2004, high precision instruments have recorded an average increase of 1.9 ppm (parts per million) in atmospheric CO2.  Between 2005 and 2014, there has been a global average increase of 2.1 ppm.  At 17 February 2015, CO2 levels were 399.97 ppm, a vast increase on 1959 levels – the first year with full high precision instrument data measurements – of 315.97 ppm, and a vast increase on pre-industrial levels of around 280 ppm.  With failures of national, regional, and local governments, as well as industry and the public to take meaningful steps to reduce emissions, levels are only set to increase.  Climate change is perhaps the most well-known consequence of our continued emissions, but of increasing concern is climate change’s “evil twin” – ocean acidification.

Not all CO2 remains in the atmosphere, with around 30% being soaked up by the ocean.  When CO2 enters the ocean it forms carbonic acid (H2CO3) which in turn breaks down into bicarbonate (HCO­3) and hydrogen (H+) ions.  Bicarbonate ions can break down even further into carbonate ions (CO23) and a hydrogen ion.  It is the increase in the concentration of hydrogen ions that increases acidity levels in the ocean.  This chemical reaction is entirely natural, and it has always taken place – just not always at such magnitude, and with such rapidity.  Since the industrial revolution, surface waters of the ocean has declined by 0.1 pH units.  This deceptively small change represents a 26 – 30% increase in ocean acidity.  Projected atmospheric CO2 levels suggest that by the end of the century, ocean pH will drop by 0.3 – 0.4 units – an increase in acidity by 100 – 150%.  Numerous studies have indicated acidification will have impacts on marine life, particularly calcareous organisms like molluscs and corals.  There is a growing body of evidence that fish are also at risk.  Laboratory experiments that attempt to determine how fish may or may not be impacted by ocean acidification typically simulate past, present, or predicted future acidity levels, and even beyond into what is generally considered impossible.  Whilst studies that suggest high CO2 levels can be lethal to adult fish typically simulate levels far above that predicted in the future, more realistic scenarios suggest that long-term sub-lethal effects are possible…

The full article was published in – and can be read in – The Marine Professional, a publication of the Institute of Marine Engineering, Science & Technology (IMarEST).

Image: The map was created by the National Oceanic and Atmospheric Administration and the Woods Hole Oceanographic Institution using Community Earth System Model data. This map was created by comparing average conditions during the 1880s with average conditions during the most recent 10 years (2003–2012). Aragonite saturation has only been measured at selected locations during the last few decades, but it can be calculated reliably for different times and locations based on the relationships scientists have observed among aragonite saturation, pH, dissolved carbon, water temperature, concentrations of carbon dioxide in the atmosphere, and other factors that can be measured. This map shows changes in the amount of aragonite dissolved in ocean surface waters between the 1880s and the most recent decade (2003–2012). Aragonite saturation is a ratio that compares the amount of aragonite that is actually present with the total amount of aragonite that the water could hold if it were completely saturated. The more negative the change in aragonite saturation, the larger the decrease in aragonite available in the water, and the harder it is for marine creatures to produce their skeletons and shells. The global map shows changes over time in the amount of aragonite dissolved in ocean water, which is called aragonite saturation. Credit USA EPA/Wikipedia (Public Domain)

Climate Change, Acidification, & the Oceans, Marine Life

A tale of two penguins

The Antarctic Peninsular is regarded as one of the fastest warming regions in the Southern Hemisphere.  It might seem small to you, but the increase in air temperature of around 2.8 degrees Celsius is resulting in some big changes.  According to the British Antarctic Survey some 25,000 square kilometres of ice has been lost from ten floating ice shelves, 87% of glacier termini have retreated, seasonal snow cover has decreased.  What exactly these sorts of changes mean for the inhabitants and seasonal visitors to the Peninsular is a question researchers are desperately trying to get a handle on.  The way each species reacts to this changing environment is likely to be very different, even among closely related species. Continue reading “A tale of two penguins”

Climate Change, Acidification, & the Oceans

A practical solution to species range changes detection?

With rapidly warming ocean regions comes changes in marine species distributions.  Understanding and monitoring these changes is important for managing biosecurity threats as well as management of existing and changing living marine resources.  Detecting range changes in the marine environment is difficult and expensive.  For many species, assessment simply has not taken place.  To combat this data gap and assist managers in directing limited research resources, Dr Lucy Robinson, research fellow at the Institute for Marine and Antarctic Studies (IMAS) and colleagues suggest a new method – rapid screening assessment that uses a variety of sources.

Development of the method, which was recently published in Global Environmental Change , focused on waters off the east coast of Tasmania, and area where over the past 50 years warming has been nearly four times greater than the global average.  Using field data from a number of sources, primarily from the citizen science program Redmap Australia, 47 species were assessed for range expansion.  Categorising species based on confidence in their range expansion, 8 species – 6 fish species, a lobster and an octopus species –  were categorised with a ‘‘high’’ confidence of potentially extending their ranges.  These species, the researchers argue, are the ones that should be prioritised for impact assessment, with those falling in the “medium” and “low” confidence categories coming after.

The paper is behind a paywall, but if you have access (or want to buy a copy) you can find it here

Image:  The rainbow cale (Heteroscarus acroptilus) is one of the species assessed in this study.  The assessment had “high” confidence in a potential range extension for this beautiful fish.  This particular beauty is a male in breeding colouration. Credit Richard Ling/Flickr (CC BY-NC-ND 2.0)

Climate Change, Acidification, & the Oceans

Rivers and streams on the Greenland ice sheet a major contributing factor to global sea level rise

Meltwater runoff from the Greenland ice sheet, which covers 80% of the country, is a major contributing factor to global sea level rise.  The processes by which melting water reaches the ocean is still a subject of research, with most studies focusing on large chunks of ice that break off the ice sheet forming icebergs, or on large lakes which can abruptly drain.  Recently, a study lead by Dr Laurence Smith, Professor and Chair of Geography, and Professor of Earth, Planetary, and Space Sciences at University of California revealed that the network of 523 rivers and streams flowing on top of the Greenland ice sheet may be draining as much – if not more meltwater through sinkholes, than the other two processes combined.

The research team utilised remote sensing, remotely controlled boats equipped with specially designed instruments, and helicopter flyovers to map the network of rivers and streams, and collect data on water flow.  Alongside the importance of rivers and networks, the study also indicated that discharge from the Isortoq River, one of the largest rivers on the ice sheet, is lower than expected given the amount of water flowing down it.  Where and how this ‘missing’ water is being captured under the surface is not yet understood, but is contrary to models used by the Intergovernmental Panel on Climate Change, which assumes all meltwater goes into the ocean.  The study will help researchers refine climate models, ultimately developing better global sea level rise projections.

The paper which was published in PNAS is open access.

Image:  Supraglacial river networks represent an important high-capacity mechanism for conveying large volumes of meltwater across the Greenland Icesheet surface.  Taken direct from the paper.