PDC Weekly Global Flood Survey: February 16, 2012

Figure 1. PDC Global Hazards Atlas displaying 7 day precipitation accumulation and PDC Integrated Active Hazards.

According to the latest NOAA prediction, the current La Nina episode has peaked, and the oceanic and atmospheric patterns now reflect weak-to-moderate strength. A transition from the recent mature La Nina towards neutral conditions will occur during the March through May 2012 period.  ENSO (EL Nino Southern Oscillation) neutral conditions refer to those periods when neither El Nino nor La Nina is present. These periods often coincide with the transition between the two events. During the ENSO-neutral phase the ocean temperatures, tropical rainfall patterns, and atmospheric winds over the equatorial Pacific Ocean are near the long-term average.

During La Nina episodes rainfall is often enhanced across the western Pacific, Indonesia and the Philippines and is nearly absent across the eastern equatorial Pacific. Elsewhere, wetter than normal conditions tend to be observed during December-February over northern South America and southern Africa, and during June-August over southeastern Australia. Drier than normal conditions are generally observed along coastal Ecuador, northwestern Peru and equatorial Africa during December, January and February, and over southern Brazil and central Argentina during June, July, and August. As we move into the upcoming neutral conditions, precipitation around the globe will likely tend back towards the average in general. This Map shows typical conditions during La Nina in February.

There are several areas around the globe that have experienced flooding events during the past week, including the Philippine Islands, Fiji, Indonesia, Peru, Ecuador, Mozambique,and Malawi (see details below).

Precipitation & Flooding: Pacific

Figure 2. PDC Global Hazards Atlas focused on the Pacific and displaying 7 day precipitation accumulation and PDC Integrated Active Hazards.

As was the case last week, we see a fairly extensive swath of precipitation extending from the East China Sea in the southwest, to the northeast across the northern latitudes of the Pacific into the Gulf of Alaska. (See Figure 2)  The bulk of this rainfall ran along the main storm track of the mid-latitudes, generally under the polar jet stream between 30 and 50 degrees north latitude. The Hawaiian Islands remained south of this rainfall.

In the south Pacific, there was a heavy swath of rainfall that moved in a southeast direction offshore from generally around the Philippine Islands, which experienced lots of flooding rainfall.  It extended over the ocean to the north of the Banda Sea, Arafura Sea, and the Solomon Sea, then further southeast to the north and northeast of the Coral Sea into Suva and Tonga.  This swath of precipitation brought locally heavy rainfall, in association with tropical cyclone (Typhoon Jasmine – 10P ) which was recently given its final warning by the Joint Typhoon Warning Center (JTWC).

Philippines Flooding:  Recent flooding rainfall has resulted in no deaths, although 13,327 people remain displaced according to the Global Disaster Alert and Coordination System (GDACS).

Fiji Flooding: According to ReliefWeb, a state of natural disaster in Fiji’s Western Division has been extended until February 19, 2012. The National Disaster Office says this will give authorities a chance to clean up areas affected by the floods before those evacuated return home. In Lautoka, Viti Levu more than 150 flood affected people remain at the Girmit Centre. The Fiji Red Cross has also been distributing emergency supplies to people affected by the floods in the Western Division. Overall conditions are improving as drier weather has dominated the past few days. Health officials are focused on the provision of clean drinking water for those homes with no water supply, as cases of diarrhea and some suspected cases of typhoid have occurred as a result of the floods.

Indonesian Flooding:  Two days of torrential rain over western-most Java has resulted in the displacement of 6800 persons. So far, no deaths have been reported by the Global Disaster Alert and Coordination System (GDACS).

 Precipitation & Flooding: Americas

Figure 3. PDC Global Hazards Atlas displaying 7 day precipitation accumulation and PDC Integrated Active Hazards.

Taking a look at North America (see Figure 3) a wide gap of generally dry conditions is evident from the west coast across the Rocky Mountains. Light to moderate rainfall fell over the northern parts of southern Mexico across the central United States.

The heaviest precipitation over South America, including localized flooding rainfall, was focused over the central part of the continent from eastern Peru across the Amazon, and throughout Brazil. Glancing south on the map, we see a second concentration of heavy, localized flooding rainfall focused on northern Bolivia.

Peru Flooding: Rains have affected 80 per cent of the Peruvian territory, according to a REDLAC report issued 13 February 2012. Since November 2011, the toll from persistent heavy rains is 49,140 people affected, 5,550 homes lost, 14 dead and 29 injured. Authorities have distributed over 94 thousand tons of humanitarian aid. During this season seven departments declared a state of emergency and on 10 February the state of emergency for the Tacna region was extended for another 30 days.

Ecuador Flooding: According to a REDLAC report dated February 13, 2012, thousands of people in the provinces of Guayas and Manabi, Ecuador are affected by flooding from the past week of rains. On 9 February, the Chone Emergency Operations Centre (COE), declared a state of emergency for the municipality. Approximately ten thousand families have been affected and are taking refuge in one of the ten temporary shelters available. In Guayas, at least 300 houses and 30 families in the Monte Sinai sector, a marginalized zone in the northwest, have been affected by the rains, according to a report from the Risk Management secretariat.

Precipitation & Flooding: Africa

Figure 4. PDC Global Hazards Atlas displaying 7 day rainfall accumulation across Africa

The PDC Global Hazards Atlas shows an area of precipitation extending from the Atlantic Ocean, inland over Equatorial Guinea, the Congo, then southward over Angola into Zambia, Zimbabwe and Mozambique…and eastward into the Indian Ocean as was the case last week (See Figure 4).  Precipitation has been particularly heavy with flooding at times, especially from Angola to Zambia and Mozambique, and then southward through Namibia, Zimbabwe and Botswana into South Africa.  Flooding was focused most intensely in and around the Benhine and Limpopo National Parks of Mozambique, and into Swaziland.

Meanwhile, active tropical cyclones in the south Indian Ocean (12S & 13S) have continued to bring more flooding precipitation to Mozambique. The PDC Global Hazard Atlas above shows these storms.

Mozambique Flooding: Tropical cyclone Giovanna (12S) brought heavy rain and flooding to parts of Mozambique during the last week, an area still trying to recover from two previous tropical cyclones in January. Giovanna is forecast to hit Zavala, Morrumbene, and Massinga in Inhambane Province, according to the National Institute of Meteorology in Mozambique. The tropical cyclone season is expected to last until March in this area. For additional information about this event, see the Global Issues report for 16 February 2012.

Malawi Flooding: According to a February 14, 2012 International Federation of Red Cross and Red Crescent (IFRC) report, Malawi continues to suffer from widespread flooding, after storms in December 2011 and January 2012 brought heavy rain which led to flash floods and destruction of infrastructure including houses, schools and churches, as well as agricultural crops. Thousands have been displaced due to flood waters and impacts to homes. Additionally, there are reported cases of cholera and fears of a possible cholera outbreak, considering that water and sanitation facilities have been greatly affected. Since December 2011, Malawi Red Cross Society (MRCS) has been responding to the affected people through provision of temporary shelter materials, including tarpaulins, using items from MRCS prepositioned stocks.

Madagascar Flooding: Tropical cyclone Giovanna crossed through central Madagascar during the past week, bringing damaging winds and flooding rainfall. Sixty-five people were confirmed dead, with over 11,000 left homeless. This tropical cyclone is continuing to spin off the country’s southwestern coast (see Figure 4). For additional information about this event, see Newstime Africa, dated February 17, 2012.

Looking Ahead

Over the next week PDC will continue to monitor areas of high precipitation and keep a close eye on flooding across the globe.  Currently PDC is monitoring flood events in the following areas: Ecuador, Fiji, Indonesia, Malawi, Mozambique, Peru and the Philippines.

For the most up-to-date information on these flood events and all-hazards, download the free PDC Disaster Alert mobile app for iOS and Android devices.