With all the undercurrents(pardon the pun) of global warming running through our media circus, I felt that it was important to touch on this subject in a way that many people didn’t think of before. Many perceive the current trend of global warming to have an immediate effect on our day-to-day weather. Well, while you may see an extra day of rain this season or unseasonably cold temperatures in the middle of April, it is far more likely that you will see dead fish washing ashore of your beaches. One of the most sensitive and accurate measurements of global climate change is at your doorstep. The Pacific Ocean is one of the largest and most diverse ecosystems this planet has ever seen and yet it is also one of the most intricately affected by minute changes in temperature worldwide.
According to the Central and Northern California Ocean Observing System (CeNCOOS), harmful algal blooms (HABs) may be coming our way soon. Recent years have shown that the types of bacteria that can cause HABs have risen dramatically(Pseudo-nitrates) and they have seen a significant increase in the amount of Alexandrium. This chemical makes saxitoxin, also known as paralytic shellfish toxin, that can cause death if people eat contaminated clams, mussels, or oysters. As you can see from the chart above, the numbers have risen dramatically since 2005.
During a HAB event, scientists generally look for 3 things:
- Presence of the organism through cell counts and DNA sampling
- Presence of a toxin
- Harm or impact on the ecosystem, economy and/ or human health
In looking for these answers, researchers can start to identify if it’s a harmful algal bloom or not, and if it is then they can ask more specific questions regarding cell abundance levels, location, distribution, and impacts. If it is not, then it’s simply deemed as a “potential” HAB event until cell and toxins reach dangerous, harmful levels.
The CeNCOOS has also taken satellite imagery over the past year and combined it into a heat map(seen at right), which shows the chlorophyll concentrations over the past four years, with red being the most extreme.
I would love to write a story on the potential impact on the fishing and canning industry, tourism, health, and overall well-being of San Franciscans that these HABs would have. It would be interesting to see how directly the global warming trend is going to impact our lives on a day-to-day basis, and how often individuals will need to adjust their lifestyles in order to remain safe.
There have been a number of other stories such as these done, but few regarding the Bay Area. For example, the LA Times did a story about millions of sardines dying in King Harbor.
And the Times-Standard up in Eureka published a story about a suspicious “brown muck” that people perceived to be an oil spill.