Climate and Harmful Algal Blooms in Lake Erie Richard P. Stumpf - PowerPoint PPT Presentation

Climate and Harmful Algal Blooms in Lake Erie Richard P. Stumpf NOAA National Centers for Coastal Ocean Science Silver Spring, MD Lake Erie 22 July 2011

2011 cyanobacteria bloom, worst in decades, visible from space 2003, “perhaps the most severe in Lake Erie’s recent history” (EPA) 09 October : Data from MERIS (European Space Agency) NOAA Coastal Ocean Science 2013 Nov Climate

2012 bloom wasn’t. 10 September, data from MODIS NOAA Coastal Ocean Science 2013 Nov Climate

Potential (Large) Areas of Concern in Great Lakes Green Bay Saginaw Bay low high 10 4 10 5 10 6 Western cells ml -1 Lake Erie 2008 bloom intensity NOAA Coastal Ocean Science 2013 Nov Climate

MERIS on the ENVISAT-1 satellite ENVISAT-1 1150 km Coverage every 2 days from 2002 to April 2012 launch of replacement (Sentinel-3) late next year NOAA Coastal Ocean Science 2013 Nov Climate

satellite algorithms (MERIS data) Standard blue-green algorithms are sensitive to absorption by many components. We use Red/NIR and curvature (shape); insensitive to sediment and CDOM NOAA Coastal Ocean Science 2013 Nov Climate

MERIS can see more wavelengths of light, allowing us to detect and quantify blooms 13 Sep 2010 True color, difficult to Red and near-infrared identify and quantify wavelengths help NOAA Coastal Ocean Science 2013 Nov Climate

This information gives a cyanobacteria index, “CI”, which equates to concentration 13 Sep 2010 low high 10 4 10 5 10 6 True color cells ml -1 Cyano Index (CI) NOAA Coastal Ocean Science 2013 Nov Climate

Bulletins for Lake Erie bloom To get bulletin, search for “NOAA Lake Erie bloom bulletin” Transports with the NOAA Great Lakes Coastal Forecast System NOAA Coastal Ocean Science 2013 Nov Climate

Annual blooms from the worst 30-day period, MERIS 2002-2011; MODIS 2012 WHO risk threshold Log-scaled display MODIS Modified from Stumpf et al., 2012 PLoSONE NOAA Coastal Ocean Science 2013 Nov Climate

Bloom severity over 11 years from satellite; sum of concentrations in western Lake Erie CI of 1 ~ 10 20 cells Microcystis NOAA Coastal Ocean Science 2013 Nov Climate

Cyanobacteria like warm water; strong growth > 20ºC; minimal growth < 15ºC Paerl et al., 2011 (Science of the Total Environment) NOAA Coastal Ocean Science 2013 Nov Climate

Climatologic Temperatures in Lake Erie Excellent growth Good growth cool Too cold NOAA Coastal Ocean Science 2013 Nov Climate

Temperature gives season but not-interannual (avg temperature over western basin) 2011 Years Years with with small large bloom bloom Stumpf et al., 2012 PLoSONE NOAA Coastal Ocean Science 2013 Nov Climate

Excessive phosphorus promotes cyano blooms Downing et al., 2001; Can.J.Fish.Auat.Sci . NOAA Coastal Ocean Science 2013 Nov Climate

Use Maumee River Discharge to make seasonal predictions; largest tributary to Lake Erie. Toledo Dayton USGS Ohio Fact sheet FS-035-96) NOAA Coastal Ocean Science 2013 Nov Climate

Understand blooms with nutrient load data 30+ year program measuring nutrients in Ohio rivers (Pete Richards, Dave Baker have led that effort) National Center for Water Quality Research NOAA Coastal Ocean Science 2013 Nov Climate

Dissolved phosphorus, has a trend but much variability Data from Pete Richards NOAA Coastal Ocean Science 2013 Nov Climate

Total phosphorus follows discharge; Spring (Mar-Jun). Maumee River total Maumee River average discharge (m 3 /s) phosphorus (m.tons) NOAA Coastal Ocean Science 2013 Nov Climate

Spring loads matter. Models predict CI (bloom severity) from spring discharge & loads. See Stumpf et al., PLoSONE 2012 Experimental SRP- Q model (based on Q model Q-P correlation) Stumpf et al. 2012 CI NOAA Coastal Ocean Science 2013 Nov Climate

2012 seasonal forecast 2012 “…calls for a smaller bloom of the cyanobacteria HAB this summer, compared to recent severe blooms. Last year’s [2011] bloom, one of the largest in decades, covered … an area the size of Long Island Sound. This year’s [2012] mild bloom is expected to about one-tenth the size of last year’s.” NOAA Coastal Ocean Science 2013 Nov Climate

Observed against model (and 2012 forecast) 2012 mild, but not as mild as model predicted observed modeled 2012 forecast NOAA Coastal Ocean Science 2013 Nov Climate

2012: Unusual in several ways. Follows 2011 (which was nearly 3x more intense than the next worst bloom) 09 October : Data from MERIS (European Space Agency) NOAA Coastal Ocean Science 2013 Nov Climate

And other unusual events, cyano bloom in central basin in early July (!) disconnected from western basin 10 July 2012 (bloom identified by Ohio EPA) NOAA Coastal Ocean Science 2013 Nov Climate

2012 had no ice 16 February, MODIS (from NASA Rapidfire) NOAA Coastal Ocean Science 2013 Nov Climate

This has happened before preceding both non-bloom years (2002 & 2005), and a bloom year (1998). (graph from Wang et al., 2012 J.Climate, Ice cover sq km) No-bloom bloom 1998 was predicted by spring load model NOAA Coastal Ocean Science 2013 Nov Climate

Lots of “unusual climate” in 2012 2012 anomalous spring diatom bloom (water supply problems) Anomalous early July central basin bloom Follows biggest bloom ever (remarkably, that hasn’t happened wet winter previously in any years) no ice NOAA Coastal Ocean Science 2013 Nov Climate

2013: model uses Maumee River spring loads (2013 load falls between 2012 & 2011) average discharge dissolved phosphorus based on USGS load (m.tons) data (m 3 /s) Maumee River total Maumee River average 2013 discharge (m 3 /s) phosphorus (m.tons) 2013 2013 Data from National Center for Water Quality Research total phosphorus load (m.tons) NOAA Coastal Ocean Science 2013 Nov Climate

2013 Forecast: Significant bloom. similar to 2003, much milder than 2011 2013 NOAA Coastal Ocean Science 2013 Nov Climate

2013 prediction for western Lake Erie “significant bloom” but 1/5 of 2011. Definitely a significant bloom. Severity to be calculated this winter. 2011 for comparison 2013 on Sep 10 low medium high concentration NOAA Coastal Ocean Science 2013 Nov Climate

Climate patterns We can estimate bloom severity. This allows for models of impacts under future scenarios (assuming other things don’t change, like invasive species, etc.) Spring load matters; caused by runoff and discharge. Precip, snow melt, etc. influence nutrient runoff. Temperature allows for blooms, but does not drive size (yet). Longer hot periods, longer blooms. >20 ºC: bloom appears; persists until <15 ºC. NOAA Coastal Ocean Science 2013 Nov Climate

Planning for climate change and variability will help the task of restoring and maintaining a Great Lake Photo from Gibraltar Island, Ohio Sea Grant Assistance from NASA Decision Support, Public Health NNH08ZDA001N NOAA Coastal Ocean Science 2013 Nov Climate