Dr. Sandra L. Cruz-PolDr. Sandra L. Cruz-Pol

INEL 4152INEL 4152

Electrical and Computer Dept.Electrical and Computer Dept.

Univ. of Puerto RicoUniv. of Puerto Rico

Module: El Niño event and the Module: El Niño event and the Ocean Surface PermittivityOcean Surface Permittivity

Remote Sensing of land/sea

The reflectivity andtransmissivity of theocean changes with theroughness of the seasurface caused by thewind, and with dielectricproperties of the waterwhich change withsalinity, watertemperature andfrequency of the observedelectromagnetic signal.This principle is used totrack El Niño phenomenafrom satellite microwaveobservations.

Earth parameterssuch as soilmoisture andgeometry of thetrees can beretrieved andstudied usingelectromagneticradiation fromactive andpassive sensors.

Passive Remote Sensing

Radiometer measures natural radiation from atmosphere & oceanatmosphere & ocean below.

Applications:Applications:•Wind speed retrievalWind speed retrieval•Wave height monitoringWave height monitoring•Sea Temperature (El Niño) Sea Temperature (El Niño) •Global change Global change

Rspec 1

Emissions and Reflections from the Ocean

• Ocean Emissivity

• Ocean Reflectivity

– where is the ocean permittivity

2

1

1

R

Permittivity of Sea Water, Permittivity of Sea Water,

The permittivity of sea water is a function of The permittivity of sea water is a function of frequencyfrequency temperaturetemperature salinitysalinity

IR jSTf ,, CCRR CCII

Case Study : El Niño

El Niño: first noticed by Peruvian fishermen who gave the name since the warm air arrived near Christmas summer (El Niño Dios visitando)

Monitoring El Niño

ATLAS buoys are deployed and used to record sea surface temperature and wind speed along the Pacific Ocean and send information through satellite.

Twin El Niño -Indian Ocean

Nearly all the elephants in Botswana’s Chobe National Park died during a drought brought on by the 1982-83 El Niño.

Bleached Coral Reefs

Corals are extremely sensitive to changes in their environment. When they die, their color disappears.El Niño events correlate with Pacific and Caribbean-wide coral bleaching.

Severe Drought SE Asia, Australia, Caribbean and CA

El Niño takes away the rainnormally present during Australia’s summer which put down natural and manmadefires.

Disease Connection: cholera, typhoid, malaria, encephalitis, dengue

Unbalance in ecosystems brings conditions that increase amounts of mosquitoes and mice.

Flooding in Brazilian rainforest. Dessert bloom and provide food to

hantavirus-carrying mice.

Hurricanes• The number of hurricanes in

the Caribbean is noticeably reduced because of the increased wind shear in different height layers of atmosphere which doesn’t allow the formation of many storms.

• During La Niña, the number of hurricanes increases, the jet stream goes North, affecting U.S. more than the Caribbean.

La Niña

Endangered species

Marine iguanas in the Galapagos usually eat redalgae. Red algae died due to high water temperatures.More than half of the iguanas died during the 1982-83 El Niño.

Magellanic penguins, which live in the coastal waters of Peru and Chile,went hungry when the fish disappeared.

Sea birds which dependon fish are directly affected by this changes.The California least ternis an endangered species.In 1988 they began to recover from 1982 Niño.

The Galapagos island sea lion went hungry. Mother spend too much time on sea looking for food, and pups didn’t get enough milk. Males don’t eat for several weeks during mating season. When back at sea, many didn’t find food to make it.

Alaskan Red Foxlives on sea birdsthat are not abundant during El Niño.

Benefits of El Niño PredictionBenefits of El Niño Prediction

Prepared for heavy rain followed by droughtPrepared for heavy rain followed by drought Now countries are measurements of Now countries are measurements of

precaution when an event is forecast.precaution when an event is forecast. Water suppliesWater supplies 85% chance of La Niña following year.85% chance of La Niña following year. produced exceptionally mild winter in NE of produced exceptionally mild winter in NE of

US. saving $$$US. saving $$$

Flooding in SW of US

Bulldozers were used to build dikes of sand on Santa Monica beach in California to protect buildings from unusually large waves

expected from 1997-98 El Niño storms.

Farming: cotton vs. rice

Benefits from El Niñoforecast in Peru includethe decision on whetherto plant rice or cotton.

Rice plants need moist to grow. (El Niño)

Cotton plants need warm dry climate. (La Niña)

Summary of Effects

• Flooding in SW of US

• Severe Drought SE Asia, Australia

• Poor fishery E of America

• Bleached Coral Reefs• Disease Connection: cholera, typhoid, malaria,

encephalitis

• Farming: cotton vs. rice

Bad NiñoBad NiñoLives lost, 189 including tornadoes, ice storm, Lives lost, 189 including tornadoes, ice storm, snow and rainstorms, drowned.snow and rainstorms, drowned.

Property losses in storms, $2.8 billion. Property losses in storms, $2.8 billion.

Federal government relief, $400 million. Federal government relief, $400 million.

State assistance, $125 million. State assistance, $125 million.

Agricultural losses, $600 million to $700 million. Agricultural losses, $600 million to $700 million.

Lost sales in snow removal equipment, $60 Lost sales in snow removal equipment, $60 million to $80 million. million to $80 million.

Tourist industry losses, $180 million to $200 Tourist industry losses, $180 million to $200 million. million.

Good NiñoGood Niño Lives saved 848, including those who survived extreme cold, snow and Lives saved 848, including those who survived extreme cold, snow and

ice storms, did not die in winter-related auto accidents and who were ice storms, did not die in winter-related auto accidents and who were not killed by hurricanes, compared to recent “normal” years. not killed by hurricanes, compared to recent “normal” years.

Reduced heating costs, $6.7 billion. Reduced heating costs, $6.7 billion. Increased sales of merchandise for homes and other goods, $5.6 billion Increased sales of merchandise for homes and other goods, $5.6 billion

as warm weather sent people to the stores to post a January-March as warm weather sent people to the stores to post a January-March retail sales record. retail sales record.

Reduced costs of removal of ice and snow from streets, $350 million to Reduced costs of removal of ice and snow from streets, $350 million to $400 million. $400 million.

Reductions in normal losses to flooding caused by melting snow and Reductions in normal losses to flooding caused by melting snow and Atlantic hurricanes, $6.9 billion. Atlantic hurricanes, $6.9 billion.

Income from increased construction and related employment, $450 Income from increased construction and related employment, $450 million to $500 million. million to $500 million.

Reduced operating costs to airlines and trucking industry, $160 million Reduced operating costs to airlines and trucking industry, $160 million to$170 million. to$170 million.

ReferencesReferences

NOAA NOAA (http://www.pmel.noaa.(http://www.pmel.noaa.gov/tao/elnino)gov/tao/elnino)

El Niño by Caroline El Niño by Caroline ArnoldArnold

A new 2002 El Niño is A new 2002 El Niño is underway! underway! http://www.pmel.noaa.ghttp://www.pmel.noaa.gov/tao/vis/tao-vis.htmlov/tao/vis/tao-vis.html

American American Meteorological SocietyMeteorological Society

The Associated PressThe Associated Press

http://www.pmel.noaa.gov/tao/vis/tao-vis.htmlhttp://www.pmel.noaa.gov/tao/vis/tao-vis.html