Monday, February 12, 2018

The inconvenience of connecting harmful algae outbreaks (HABs) and Climate Change

Though Climate Change is moving quickly through New York and other regions, it’s still difficult for scientists to evaluate the precise consequences because changes in climate still take decades to play out. We know that our heavy rainfall events have increased 71% since 1958, for example, but we still don’t know the exact relationship between the recent outbreaks of harmless algae, harmful algae outbreaks (HABs), and Climate Change.

HABs are a danger to our drinking water, our pets, our shoreline properties, swimming beaches, and much more. [Check out Harmful Algal Blooms (HABs), by the New York State Department of Environmental Conservation)

We know that there has been a dramatic increase in HABs in our Finger Lakes region.

“Unseasonably warm days in early and mid September have fueled a surge in harmful algal blooms, or HABs, in New York’s Finger Lakes, firmly establishing 2017 as the region’s worst year on record. Last year, the often toxic green scum was reported on the surface of six of the 11 Finger Lakes — then the most ever. This year, its been spotted on all 11.” (Posted on September 20, 2017 Water Front)

We know there’s been an increase in algae blooms in the Great Lakes, especially in Lake Erie. Though most algae outbreaks aren’t harmful (although the 2014 HABs outbreak in Toledo, Ohio certainly was), NYS’s environmental agency points to phosphorus, nutrient enrichment, aquatic invasive species—and Climate Change as the culprits.

 “What is causing the algae problems in Lake Erie? Lake Erie is the shallowest of the Great Lakes, the warmest, and the most susceptible to eutrophication (nutrient enrichment) and the effects of climate change. Lake-wide changes have occurred in Lake Erie due to phosphorus enrichment from both rural and urban sources, compounded by the influence of climate change and aquatic invasive species.” (Overview of HABs and Drinking Water in NYS, 2014, New York State Department of Environmental Conservation (DEC))

What we don’t know is the exact cause-and-effect relationship between any specific lake’s HABs outbreak and Climate Change. This 2013 factsheet from the Environmental Protection Agency (EPA) gives some insight into this HABs/Climate Change relationship, but hasn’t nailed it down:

Impacts of Climate Change on the Occurrence of Harmful Algal Blooms Climate change is predicted to change many environmental conditions that could affect the natural properties of fresh and marine waters both in the US and worldwide. Changes in these factors could favor the growth of harmful algal blooms and habitat changes such that marine HABs can invade and occur in freshwater. An increase in the occurrence and intensity of harmful algal blooms may negatively impact the environment, human health, and the economy for communities across the US and around the world. The purpose of this fact sheet is to provide climate change researchers and decision–makers a summary of the potential impacts of climate change on harmful algal blooms in freshwater and marine ecosystems. Although much of the evidence presented in this fact sheet suggests that the problem of harmful algal blooms may worsen under future climate scenarios, further research is needed to better understand the association between climate change and harmful algae. May 2013 US Environmental Protection Agency Office of Water EPA 820-S-13-001 MC 4304T

There are many reports* besides the above one that suggest that warmer waters and/or Climate Change have and will play a role in more HABs in our lakes, endangering our health and environment. But most local media reports don’t reflect the possibility that the worldwide warming crisis could be affecting our region in this ominous way--now.

There are and should be a concerted effort to reduce phosphorus, nutrient enrichment, aquatic invasive species coming into our lakes. But it appears quite likely that HABs won’t get under control until we factor in, however inconvenient, Climate Change.

Shouldn’t we at least try and rule out Climate Change? Seems prudent. Avoiding the possible Climate Change connection in the rise in HABs would be like getting up in the morning and finding your backdoor wide open and just assuming it was the wind. Maybe it was the wind, someone could have forgotten to close the door. Or, it could have been a burglar. In which case, if there was only a slight chance someone broke into your house and was still prowling about, wouldn’t you want to check that out? Same kind of need to discover (if any) the connections with Climate Change and environmental anomalies.

Despite much certainty about Climate Change—our planet is warming, it’s us—there is also a lot of uncertainty about how the extra energy captured by our greenhouse gas emission radiates through our natural systems. Glaciers are melting, but how fast? And, how much does more water entering our warmer lakes affect the increase in algae outbreaks—let alone harmful algae outbreaks? In other words, does Climate Change amplify the known causes that lead to HABs? Not to mention, what else besides Climate Change could account for all the Finger Lakes getting hit by HABs recently?

The media, craving certainty and not upsetting their subscribers with what they perceive as speculations, are not likely to press Climate Change in an interview about HABs unless the interviewee makes a point of it. And the public isn’t going to demand that their media connect the dots between local indicators of climate Change and HABS until the public is comfortable with such discussions.

If Climate Change is warming our lakes (it is), can we address the HABs situation if we don’t also address Climate Change?

Time passes.

* Besides the EPA information fact sheet above, there are other sources out there on the relationship between Climate Change and HABs:

  •  Harmful algal blooms and climate change: Learning from the past and present to forecast the future (2015 US National Library of Medicine Nation Institutes of Health)
  •  Factors that Promote Growth of Harmful Algal Blooms “Changes in water temperature, particularly increases in temperature” (Centers for Disease Control and Prevention (CDC))
  • “Rising air temperatures can also lead to declines in water quality through a different set of processes. Some large lakes, including the Great Lakes, are warming rapidly.30 Warmer surface waters can stimulate blooms of harmful algae in both lakes and coastal oceans,9  which may include toxic cyanobacteria that are favored at higher temperatures.31”(“ Climate Change Impacts in the United States” (Page 198, National climate Assessment 3rd report)
  •  “Over the course of the 20th century, regional seasurface temperatures have risen more than 1.0ºF. Water temperature changes can result in shifts in faunal assemblages (groupings of organisms) that affect marine ecosystems and economic activities in unknown ways. Every species has a thermally suitable range for habitat that, when compromised, induces a forced migration to seek another location suitable to its life cycle. Water temperatures influence organism survival and growth, 126 ClimAID egg and larvae development, and spawning and feeding behavior. When water temperatures rise, ecosystems become vulnerable to shellfish diseases, harmful algae blooms, and exotic species that force indigenous species to compete for resources, including dissolved oxygen (DO). Oxygen solubility will decrease as water temperatures increase, further stressing marine organisms.” (pages 125, 126 Responding to Climate Change in New York State (ClimAID(, full report)
  •  Massive Toxic Algae Blooms May Prove a Sign of Climate Change to Come The blooms off the U.S. West Coast may become more frequent (2015 Scientific American)

  •  “Climate models project decreases of renewable water resources in some regions and increases in others, albeit with large uncertainty in many places. Broadly, water resources are projected to decrease in many mid-latitude and dry subtropical regions, and to increase at high latitudes and in many humid mid-latitude regions (high agreement, robust evidence). Even where increases are projected, there can be short-term shortages due to more variable streamflow (because of greater variability of precipitation) and seasonal reductions of water supply due to reduced snow and ice storage. Availability of clean water can also be reduced by negative impacts of climate change on water quality; for instance, the quality of lakes used for water supply could be impaired by the presence of algae producing toxins.” (page 251 Part A Scholarly articles for IPCC Climate Change 2014: Impacts, Adaptation, and Vulnerability)

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