Bongor synoptic station (Chad). It

stopped operating since the beginning of 2013

as a result of acts of vandalism and pillaging

on measurement instruments in the park.

Empty meteorological shed of Bongor

The last data of the station dated April to

October 2012, when the total recorded rain-

fall amounted to 1152.2mm.

At LCBC, Bongor is a key station for the cli-

mate surveillance in the Yaeres which are

important floodplains shared by Cameroon

and Chad. These Yaeres offer a lot of envi-

ronmental services to the region: rice gro-

wing, recharge of water table, habitat to mi-

grating birds, etc.

Rainfall, temperatures and evapo-

ration at Moundou station (Chad). Rainfall recorded at Moundou started too slo-

wly at the beginning of March 2013 then in-

tensified from May to June.

Synoptic situation

Hydrometeo Bulletin , 2nd Quarter, 2013 Page 1

HYDROMETEO News Bulletin, 2nd Quarter 2013 of Lake Chad Basin Observatory (Lacbo)

SUMMARY

Synoptic situation ...………………………...……... 1

Regional climatological situation .…………….2

Hydrology/Hydrogeology..…………………………..3

Event of 2nd Quarter, 2013 ……………….......4

Photo Lacbo

The total amount of rainfall by the end of the

2nd quarter, 2013 is set to 381.5mm.

Rainfall at Moundou, January-June 2013

The mean temperatures under shade rather lo-

wered after April, this seems logical for such pe-

riod. The maximal temperature was then 31,5°C

in April while the minimal temperature was

27,3°C in June.

The Pich evaporation followed also this down-

ward trend, but in a more rapid manner due to

the fast increase of the rainfall in June 2013.

The Pich evaporation reached 410 mm in Janua-

ry, and 137 mm in June.

Rainfall, temperatures and evapora-tion at Sarh (Chad)

Meteo-airport Station of Sarh

The main climatological parameters observed at Sarh are carried out at meteo-airport Sta-tion, with coordinates 09°08N and 18°22E. Between January and June 2013, the synoptic station recorded in total 342.8 mm of rainfall out of which the most important is in June.

Evaporation and rainfall at Sarh, January-June 2013

The mean temperatures under the shade va-ried between 32,1°C in April and 27,6°C in Ju-ne.

The Pich evaporation has followed the same evolution as for the temperature`s one, de-creasing from 199mm to 112mm at the same period. Generally, this evaporation decreases when the rainfall increase and vice-versa.

Seasonal precipitations. The seasonal

precipitations of March-April_May (MAM) show

a situation above the normal in the major part of

Nigeria, South of Chad, North of CAR. It is rela-

tively high in the regions of Moundou, Maroua

and Maiduguri.

Seasonal precipitations (%) MAM 2013 (Source : NOAA/NCEP)

Level of Lake Chad at Bol. The Lake

Chad follows its seasonal descent which star-ted last last December. As to 30th June 2013, its level reached 125cm against 52cm at the same date in 2012. Though the rainfall is nil at Bol-Bérim station in June, the Lake maintai-ned a level two times higher to that of 2012.

Levels of Lake Chad at Bol, January-June 2013 and January-

December 2012

Hydrométéo Bulletin , 2nd Quarter, 2013 Page 2

Regional climatogical Situation

Hydrology/Hydrogeology

Chari river at Sarh. The daily evolution of

river Chari levels at Sarh was observed from March to June 2013 and compared with the evo-lution of 2012 at the same period.

Daily evolution of Chari level at Sarh

This evolution reveals that the river level ascends very slowly this year. This ascent took place en May rather than in April as it was the case in 2012, leaving therefore one month delay.

Logone station at Bongor. The monitoring

of the water level was not effective in this sta-tion between March and May 2013 during recee-ding period as a result of absence of the zero point of the staff gauge. This situation is unfortu-nately frequent within the hydrological networks of the Lake Chad basin .

Points 3 and 4 of staff gauge, Bongor station

In 2012, the Logone level reached 447cm, a level much higher in 2010. In the two cases, serious floodings occurred in the region.

Daily evolution of Logone level at à Bongor

Logone station at Moundou. The access to

this station is sometime difficult because the site

serves both for storing construction sand and for

connexion point with the opposed bank by canoe.

The daily evolution of Logone river at Moundou

was carried out between 1st May and 30 June

2013. This evolution is then compared with that of

June 2012 (the station data being not fully availa-

ble). We may observe a significative ascent of the

Logone level in June, two months after the rain-

falls.

Hydrométéo Bulletin , 2nd Quarter 2013 Page 3

Daily evolution of the Logone level at Moundou

Discharge measurement at ADCP. For its 2013 strategic programme, the BGR-LCBC Project considered the Logone river floodplain as a pilot area. It is a matter to carry out investigations so as to understand the inter-action between surface and ground waters in the region. In order to have the most recent data on Cha-ri and Logone discharges, a set of rules were carried out by the project in April 2013, using Acoustic Doppler Current meter Profiler (ADPC). The sites concerned were about four: Chari River at N’Djamena-TP and at Mailao, Logone River at Logone Ngana and at Bongor and Kalambou river (Logone tributary) at Nga-na.

The results show that the discharges obtained are generally lower (10-50%) than those calcu-lated by DREM from the rating curve. The pro-ject therefore recommended DREM to use mo-re often the ADCP tool in order to carry out corrections on these regular discharges mea-surements. BGR/LCBC Project

Meeting on the Inter-basin Water Transfer Project. A setting up contact mee-

ting between members of committee in charge of the water transfer project from Oubangui to Lake Chad took place in the conference hall of the Central Africa Development Bank at Braz-zaville, Congo from 11 to 12 June. This com-mittee was established to enable the Oubangui-Sangha International Commission (CICOS) and the Lake Chad Basin Commission (LCBC) to jointly monitor the project.

Family Photo, LCBC/CICOS

The meeting enabled the CICOS and LCBC ex-perts to exchange on the terms of reference of the impacts study of water transfert to Congo basin. A short term programme on mee-tings was then prepared.

Hydrométéo Bulletin , 2ème trimestre 2013 Page 4

Event of 2013 2nd Quarter

Logone Floodplain Reading committee: Sédick Ahmed, Boubakari

Mana, Eric C. Moutadé, Aminu B. Magagi,

Assana Abani and Abdou Mohamed

For any comment, suggestion or question on this News Bulletin, please write to: LCBC PO Box 727; E-mail: cab@cblt.org Contact: Michel DIMBELE-KOMBE, Director of Observatory; E-mail: mdimbelekombe@Yahoo.fr

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