Methods of Detection of Change and feedback analysis

Methods of Detection of Change and feedback analysis in Ocean processes Jose Luis Santos, Ph. D. National Center of Coastal Resources jlsantos@espol. edu. ec Escuela Superior Politecnica del Litoral Guayaquil, Ecuador

1. Introduction (Problems and constraints) 2. On the use of indicators. 3. On detecting changes in the Ocean. 4. On the (feedback) processes occurring in the Ocean. 5. Closing Remarks

1. Introduction (Problems and constraints) Problems in detecting Change: • Meteorological measurements from the past, and most measurements being made around the world today, originate from simple, manual instruments developed a century or more ago. • Over the oceans we have virtually no long-time continuous measurements of precipitation, evaporation, or radiation. • Data not readily available (political, military , economical reasons) • Even the most sophisticated climate models are not yet able to predict what the real-world climate will do • Development of data loggers, able to record automatically measurements made by precision electronic sensors and to telemeter them from anywhere on Earth Cost!

2. On the use of indicators. • Main function of an indicator is to communicate information and therefore, it consists of a value derived from a measurement or series which provides information about the state of the climate • Ideally, the indicators would form part of an Early warning System for the rapid detection of changes in climate • Indicators for climate change and water quality, may look at biological, physical, social or economic parameters. • Very often these indicators are chosen for their appeal to the public

Example of ECN data used to disaggregate national indicator to local (site) level. (http: //www. ecn. ac. uk/CCI/cci. asp)

UK Climate Indicators Indicator Climate Variable Physical Sea surface temperature in the Irish Sea N/A Biological Occurrence of bottom living sea fish Sea surface temperature Barnacle abundance Sea surface temperature Plankton abundance Strength of westerly circulation in winter Phytoplankton colour Sea surface temperature

European Environment Agency Indicators of Climate Change Temperature Characteristics Storm Surges Water Availability Precipitation Forest Growth Plant Phenology North Atlantic Oscillation Sea Level Rise Coastal Erosion and Retreat Greenhouse Gas Concentrations Thermohaline Circulation of North Atlantic Temperature of Intermediate Layer (Baltic Sea) Storms/Storm Events # of Skiing Tourists in Winter Sea Surface & Lake Temperature Lightening Frequency Forest Suitability Crop Suitability # Weather-related Catastrophic Events (Insurance) Cool and Shrinking of Strato- Marine Ecosystems and , Meso- and Thermosphere Biodiversity (Zooplankton) Catastrophic Weather Events (Floods, storms) Snow Cover Sales of Seasonal products Disruption of Transport Mountain Glaciers Shift in Tree Line Pests and Diseases Arctic Sea Ice Extent and Duration Discharge form Small Undisturbed Watersheds Seasonality of Hay Fever (Pollen &Allergic Disorders) Permafrost/Profiles of Temperature Change in Ecosystem Composition/Biodiversity Distribution of Vector-borne Diseases Lake and River Ice Net Carbon Uptake (NEP) Vector Distribution Baltic Sea Ice Ecosystem Fires Death Attributable to Heat Soil Moisture Availability Annual River Discharge Growing Season Length Energy Consumption for Space Heating in Winter Frequency of Low and High River Flows Seasonal Peak of Flood and Water Borne Diseases

3. On Detecting the changes in the Ocean. • In recent years, reports on marked changes in plankton and fish populations due to climate changes. • Indication that these changes are not linked to primary productivity of the ecosystem, as once supposed, but are more subtly connected to temperature changes and their influence on ocean currents, possibly through competition between species. • Because of their sessile character and relatively long life-span, benthos integrate environmental fluctuations and influences at a particular place over a relatively long time span, thus it makes benthos a suitable indicator for changes in environmental quality.

• Increases in both troposphere temperature and water vapor concentrations are among the expected climate changes due to variations in greenhouse gas concentrations. • However both increments could be due to changes in the frequencies of natural atmospheric and oceanic circulation regimes. • While much attention is being given to global warming and global climate change, it is important to know that heating of the Earth’s surface can’t be judged simply by air temperatures. Humidity holds heat that is not directly measured by air temperature, which can affect how we measure the heat content at the surface of the Earth. • Past studies have analyzed together the pair temperature-humidity to diagnose climate change. A way of quantifying both magnitudes in a single variable consists of using equivalent temperature, defined as the temperature that an air parcel would have if water vapor were condensed out at constant pressure, the latent heat released being used to heat the air. • Is a global- or a zonally-averaged surface air temperature an effective metric of the Earth’s radiative imbalance? • Is a global- or a zonally-averaged surface air temperature an effective metric of climate change?

• Does ocean heat content changes provide a more robust metric of the Earth’s radiative imbalance? Pielke Sr. , R. A. , 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc. , 84, 331 -335. http: //blue. atmos. colostate. edu/publications/pdf/R 247. pdf • Do spatial analyses of regional trends in tropospheric temperature, winds and humidity provide a more robust metric of the atmospheric component of climate change and variability? Chase, T. N. , J. A. Knaff, R. A. Pielke Sr. and E. Kalnay, 2003: Changes in global monsoon circulations since 1950. Natural Hazards, 29, 229 -254. http: //blue. atmos. colostate. edu/publications/pdf/R 239. pdf

Seasonally-averaged 1982 -1997 differences between TE trends and T trends for all individual trends (black bars), individual trends that are at least 90% significant (dark gray bars), individual trends that are at least 95% significant (light gray bars), and individual trends that are at least 99% significant (stippled bars). Error bars indicate standard errors. For each computation, each station is weighted equally. (Pielke, 2003)

Annually-averaged differences between TE and T trends for 19821997, as a function of the land-cover classes. Error bars indicate standard errors. All individual trends are considered. (Pielke, 2003)

Thus: The Metric of Assessing Climate Change Using a Global Surface Temperature Trend Should be Replaced By A Metric that Assesses Atmosphere and Ocean Circulation Variability and Change

4. On the (feedback) processes occurring in the Ocean. • The rate of global warming and the spatial distribution of warming are influenced by the uptake of heat by the oceans. • SST is set by the ocean's heat uptake from the atmosphere; upper ocean stratification, which depends on temperature, salinity, and winds; and ocean currents, which are driven by the atmosphere. • SST is in turn a surface boundary condition for the atmosphere, impacting largescale atmospheric wind patterns, most directly in the tropics, and impacting storm tracks and intensity at mid-latitudes. • Ocean surface temperatures also impact ice cover at high latitudes and thus influence albedo, which influences the atmosphere and hence the ocean temperatures. Poor knowledge of all these processes and consequently their parameterizations in climate models contribute to widely varying climate model projections.

• Coupling and feedback between ocean processes and the atmosphere involves the ocean's dynamical state, including overturning, mixing, and stratification in the ocean's surface layer, as well as movement of heat and freshwater from one region to another, horizontally and vertically, mainly driven by the winds. Significant portions of even thermohaline (conveyor) circulation are windforced, through advection and upwelling in the upper ocean. • To the extent that the atmosphere is sensitive to ocean conditions, the winds are then affected and in turn force the ocean, the necessary ingredients for feedback. For example, changes in the strength of the Arctic oscillation may affect the strength of the overturning, which could in turn feed back on the strength of the Arctic oscillation. • Direct atmospheric sensitivity to the oceans is generally strongest in the tropics. At higher latitudes sea-ice cover and hence albedo is an important factor, and thus climate is indirectly sensitive to ocean conditions affecting sea ice at these latitudes.

Change in Mean annueal Temperature, 30 years after the colapse of thermohaline circulation. (M. Vellinga, Hadley Centre. )

• The best-known and possibly strongest climate feedback involving the ocean, on interannual time scales, is the El Nino. Southern Oscillation (ENSO), which is centered in the equatorial Pacific and produces a strong interannual climate variation that impacts a large portion of the globe. • Global Climate Effects occur with ENSOs for the Following Reasons: 1. Large Magnitude 2. Long Persistence 3. Spatial Coherence

Oceanic Niño Index (ONI) • Based on the principal measure for monitoring, assessment, and prediction of ENSO (SST departures from average in the Niño 3. 4 region) • Three-month running-mean values of SST departures from average in the Niño 3. 4 region, based on a set of improved homogeneous historical SST analyses (Extended Reconstructed SST – ERSST. v 2). The methodology is described in Smith and Reynolds, 2003, J. Climate, 16, 1495 -1510. • Used to place current conditions in historical perspective • NOAA operational definitions of El Niño and La Niña are keyed to the index.

The last 3 El Niño Events, as defined by NOAA: AMJ 2002 – FMA 2003 JJA 2004 – JFM 2005 ASO 2006 – DJF 2007 Have produced virtually no climate effects on Ecuador

Wolter and Timlin, 1993, 1998 attempt to monitor ENSO by computing a Multivariate ENSO Index (MEI) based on the six main observed variables over the tropical Pacific. These six variables are: sea-level pressure (P), zonal (U) and meridional (V) components of the surface wind, sea surface temperature (S), surface air temperature (A), and total cloudiness fraction of the sky (C).

5. Closing Remarks The dangerous changes in the climate change system keep resulting and threatening our own civilization, we must remember that Nature, climate and climate change system are no simple systems (features, entities, and processes), but complex and complicated, and our approach to study them should always need to take this fact into account.

• The Future of Climate Science Climate is an integration of physical, • chemical and biological processes Climate involves the oceans, atmosphere, land surface, and continental ice • We need to move beyond the current narrow focus of climate change as equivalent to “global warming. ” • We need to deemphasize the globally averaged surface temperature as a climate change metric and assess instead circulation changes as defined by tropospheric temperature and water vapor (and for the ocean, temperature and salinity) variability and trends.