Importance of Meteorological Information in Locust Forecasting Models G. Maracchi and L. Genesio IBIMET-CNR Consiglio Nazionale delle Ricerche WMO, Geneva,

Importance of Meteorological Information in Locust Forecasting Models

G. Maracchi and L. GenesioIBIMET-CNR

Consiglio Nazionale delle Ricerche

WMO, Geneva, October 18, 2004

Biological cycle of desert locustSchistocerca gregaria (Forskal).

Solitary Adult

Hopper(5 juvenil stages)

Gregary egg laying80 eggs

Gregary Adult

Solitary egg laying90-150 eggs

Eggs

3 to 5 generations per year in Africa

swarms

hatching

migration

Recession

• In recession periods desert locusts concentrate in semi-arid and arid regions of Africa, near East and south-West Asia

• In plague periods they expand over enormous areas covering the 20% of the total surface of the world

Plague


G. Maracchi and L. GenesioWMO, Geneva, October 18, 2004

A biblical plague• Pharaonic times plagues • Plagues in Europe reported in 18th century• Twenty century plagues: 1926-1934; 1940-1948;

1949-1963; 1967-1969; 1986-1989; 2003-2004• In 2004 around 4 million hectars have been

infested in West Africa. The infestation extended from Sudan to Cape Vert. More severely affected countries: Mauritania, Niger, Mali and Senegal.



Migratory movements

Spring Autumn

source FAO



Importance of meteorological parameters in desert locust cycle

• In the reproduction phase : soil humidity for eggs opening

• In the juvenil phase (hopper) : rainfall amounts favourable for vegetation growth accelerate instar development supporting large populations of young locusts

• In the migratory phase : wind driven movements



Rainfall amounts in the reproduction phase

• Are important for the hatching phase and for hopper development (vegetation growth)



Favourable conditions for eggs laying and hatcing

Data source Elaboration: IBIMET-CNR

Early start of rainy season in the Sahel



Weather driven migration

• Desert locust fly with the winds over long distances:– 1954 : North-Africa to British Islands– 1988 : West-Africa to the Caribbean (5000km)



Skyways (Vertical Wind Anomaly)

Small infestations in Mediterranean Europe were reported in 2003 and 2004 summer associated with favourable winds

2003 2004



Skyways in May 2004



Climate sensitiveness of locust

Climatic caracteristic of peak years

• Favourable winds direction and persistence

• High rainfall amounts at the beginning and at the end of the cropping season in Sub-saharian Africa (start and lenght of cropping season)

• High rainfall amounts in Spring in North Africa



The high inter annual variability in locust infestation is mainly due to the

high climate sensitiveness of their reproduction and diffusion phases

Climate sensitiveness of locust



Parameters for predictability in different lifecycle phases

• Reproduction phase: – Soil humidity– Vegetation development– Lenght of the cropping season in the Sahel

• Migration phase: – Wind– Vegetation



Time scales and tools for prediction

• Short term forecasting

• Medium term predictions

• Long term predictions



Short term monitoring

• Monitoring of NDVI anomaly (NOAA, Spot Vegetation)

• Rainfall estimates (Meteosat)

The continuous monitoring of rain and vegetation conditions provide important information for monitoring Desert Locust

habitats and forecasting locust development



Seasonal vegetation development



Seasonal vegetation development in southern Mali – AP3A Project

Short term monitoring

NDVI anomaly over north-Africa and sahel in 2004

Source NASA



Short term monitoringHOWI zone 3 (Mauritania)

Humidity anomaly in the early season



Short term monitoringRainfall estimates from satellite



Short term monitoring6 hours rainfall estimates from satellite

April 29, 2004, 06h00

April 29, 2004, 12h00

Short term monitoringRainfall estimates from satellite



Animation sequence every six hours Oct 13-15, 2004 www.ibimet.cnr.it/Case/sahel/

Short term monitoringRainfall estimates from NWM



Rainfall estimates from NWM(96 hours

forecasting)

Medium term predictionsCrop season forecasting Risk Zones ZAR (AGRHYMET)



Medium term predictions









Long term prediction

Seasonal forecasting:• SST• Geopotential height• ITCZ• HOWI Hydrological Onset and Withdrawal Index

• Previous season late rains



Sea Surface Temperature



Geopotential Anomaly



Hadley CellMass streamfunction [1E10 kg/s]

(NCEP/NCAR Reanalysis 1971-2002)

Hadley, Ferrel and polar cell

Changes of Hadley cells affect the descending

branch of ITCZ

Seasonal migration of descending branches of Hadley cell

Seasonal migration of

ITCZ

ITCZ follows sun declination







• To optimize actions to fight infestations: – On time pesticide availability– Avoiding of accumulation of potentially obsolete

pesticide stocks– Planning of Airplanes campains

• To provide information for the Food crisis prevention process

• To provide an assessment of potential impact on food security

Objectives for a meteorological warning systems for locust control

(MeWaLCo)



The food crisis prevention process

The food crisis prevention process: Regional crisis Scale of

event

(frequency)

Potentially affected

population

Impact

Information and actions

May June July Aug

Regional scale

famine

(1 year every 10)

Million of inhabitants

Survival depends on food aid and

on International

Organisations

PRESAO Warning

ITCZwarning

and international mobilisation

ZAR, SISP Prediction,

terrain missions to identify the

dimension of the crisis; Logistical

planning for food aid

Identification of vulnerable areas;Stock distribution

Crisis prevention

Crisis management



Impact assessment

The impact of outbreaks must be evaluated in function of the vulnerability

context of the affected territory





Information flow for an information system for locust control

Choc

Agricultural campaign monitoring

Identification of vulnerable zones and groups

(regional/national/local)

Production of scenarios

Decision making

Control actions

Monitoring of impacts

Start of locust outbreaks

Production/diffusion of information



Availability operational tools

• Many decision support systems for food security already provides operational imputs that can be useful for locust monitoring

• The “convergence of evidence” methodology can be applied to locust early warning



Climate changes and locust changesNDVI trends 1982-2000 - first decade of May

Data NOAA-AVHRR – elaboration IBIMET CNR



ConclusionsThe Locust Control process needs operational tools

over different periods of the year:- Early seasonal prediction- Crop season monitoring (start and lenght)- Rainfall estimation from satellite- Rainfall estimation from NWM- Biomasse estimation - Impact matrix assessment

All these tools are developed by IBIMET CNR in the framework of MeWaLCo Pilot Project



Documents

Importance of Meteorological Information in Locust Forecasting Models G. Maracchi and L. Genesio IBIMET-CNR Consiglio Nazionale delle Ricerche WMO, Geneva,