Monterey Bay Time Series - El Niños during and Transition from El Viejo to La Vieja - The age of dinoflagellates?

Biological Consequences of Climate Change Francisco Chavez Senior Scientist MBARI February 2007

An Introduction to Anomalies

Behrenfeld et al., Nature 2007 The Length of the Record is Important

Presentation also makes a difference

An unusual winter, is it Climate Change aka Global Warming

What is Climate Change? Depends on who you ask It is not only global warming, but any change in climate, be it due to nature or man, on any scale (e.g. interannual to centennial or longer)

National Academies Report 2006 Little Ice Age

“The extended reconstructed sea surface temperature (ERSST) was constructed using the most recently available International Comprehensive Ocean-Atmosphere Data Set (ICOADS) SST data and improved statistical methods that allow stable reconstruction using sparse data. This monthly analysis begins January 1854, but because of sparse data the analyzed signal is heavily damped before Afterwards the strength of the signal is more consistent over time”ICOADS

Unfortunately SST is our only long term instrumental record in the ocean Upwelling regions account for 1% of the ocean but ~50% of the global fish production

Small Pelagics Fisheries Ocean Thermal Dynamics and Circulation Atmosphere and Climate Macronutrients plus iron Zooplankton Primary Productivity Freshwater fluxes Surface Warming Precipitation, wind, dust supply Recruitment Mortality and Predation Habitat and distribution Climate Change and the Abundance of Small Pelagic Fish

Reynolds and Smith, Strong Northern Hemisphere Bias in Recent Warming – effects not uniformly distributed

Let’s take out the trend and look at the residual variability – First EOF of global SST

Pacific Decadal Oscillation (PDO) All of these were calculated exactly the same way as the PDO. So ……

Should it be the Global Multi-decadal Oscillation? Regime shift

El Viejo La Vieja El Viejo La Vieja MBARI time series Child El NiñoLa Niña Parent 1900 to 2000 It is a familiar story

Monterey Primary Production Monterey Chlorophyll CalCOFI Chlorophyll 1984 to present California has become more productive!

The Sea Level Story

Monterey Bay Temperature at Depth Monterey Bay Surface Chlorophyll Monterey Bay Nitrate at Depth Local Ocean ecosystem responds to large scale forcing Temperature at 60 meters Nitrate at 60 meters

Monterey SST Monterey Dinoflagellates Monterey Temperature at Depth Forcing from above?

A fly in the ointment? The prevailing thought is that when the world warms ecosystems become less productive The developing paradox of what happened during the Little Ice Age

The northwest African margin is a coastal upwelling system. Sea surface temperature (SST) records from Moroccan sediment cores, extending back 2500 years, reveal anomalous and unprecedented cooling during the 20th century, which is consistent with increased upwelling. Upwelling-driven SSTs vary out of phase with millennial- scale changes in Northern Hemisphere temperature anomalies (NHTAs) and show relatively warm conditions during the Little Ice Age and relatively cool conditions during the Medieval Warm Period. These results suggest that coastal upwelling may continue to intensify as global warming and atmospheric CO2 levels increase. McGregor, Dima, Fischer, Mulitza Science, 2/2/2007

Paleopeces (unpub. data) Fish Scale Record from a core off Peru – Surprise, the anchovy and other fish disappear during the Little Ice Age Little Ice Age

El Niño Same thing during El Viejo Warmer coastal upwelling and warmer world

A developing Paradox Observations from the modern record show that the entire globe warms during El Niño and El Viejo and in coastal upwelling systems (at least in the Pacific) temperature goes up and productivity goes down. The opposite seems to happen during the Little Ice Age when the coastal upwelling system off NW Africa warmed and the coast of Peru became less productive. We must be looking at very different mechanisms …. Will there be more fish in a warmer world?