ECE Phase I
Vietnam Start-Up Workshop on Understanding Extreme Climate Events
29-30 April 1999
Hanoi

A start-up workshop for the Program on Understanding Extreme Climate Events in Vietnam was held on 29-30 April 1999 in Hanoi, Vietnam. The workshop, organized by the Disaster Management Centre of the Department of Dyke Management on Flood and Storm Control of the Ministry of Agriculture and Rural Development, in collaboration with the Asian Disaster Preparedness Centre (ADPC), was attended by 34 participants from different departments and agencies dealing with the consequences of extreme climate events in Vietnam.

The main objectives of the workshop were :

• to finalize an implementation plan for the Program on Understanding Extreme Climate Events in Vietnam; and

• to brainstorm on the different components of this implementation plan and obtain strategic guidance from the key stakeholders.

  An indicative implementation plan for the program identified:

• The key issues that the program should address (what should we look at );

• Appropriate institutional contacts for information gathering and dissemination (who will do what?); and Appropriate time frame for various activities (what time frame?)

top^

Structure of the Workshop

The two-day workshop was mainly divided in two parts:  

• Presentations by some of the key agencies representing the sectors affected by the impacts of extreme climate events in Vietnam. These presentations helped in highlighting the key issues that need to be addressed by the program in each sector.

• Focused group discussions (two groups) were formed to finalize the implementation plan for the program. Group I consisted of technical experts. Group II consisted of policy/ decision-makers. Representatives of ADPC assisted the groups in their discussions.

  ---

top^

Summary of Discussions

The climate of Vietnam is governed by the following major wind patterns and cold front movements :

• Northeasterly winds ¡ Coastal region of Central Vietnam ¡ August-December

• Southeast monsoon current ¡ North and Central Vietnam ¡ May-October

• Southwest monsoon current ¡ South Vietnam ¡ April-September

• Cold front movements from Siberia ¡ North Vietnam ¡ Winter-Spring season

The ENSO impacts on the monsoon usually affect :

• Position of Inter-Tropical Convergence Zone (ITCZ)

• Dates of onset and termination of rains

• Intra-seasonal variation of rains with clusters of wet and dry spells

• Typhoon and tropical depression incidences

The climatic variability-related natural hazards are:

• Winter-spring drought in North Vietnam

• Winter drought in South Vietnam and highlands of Central Vietnam

• Hot dry weather in summer over coastal plains of Central Vietnam leading to summer droughts

• Typhoons/ floods/ storm surges and inundation in varying magnitude and frequencies affecting most of the provinces in North, Central Vietnam.

• Saline water intrusion either by low flow of rivers due to drought or typhoon/ storm surge forced intrusion.

• Impact of temperature variations affecting winter, spring rice productivity in North Vietnam.

• Forest fires in highlands of Northern and Central Vietnam

Differential ENSO impacts ¡ space and time

• Although there are discernible linkages between ENSO and the above-mentioned climate variability related impacts in Vietnam, ENSO events do not affect Vietnam uniformly and the impact varies from area to area and event to event.

• While more number of tropical depressions and typhoons tend to affect Central and Southern parts of Vietnam during cold ENSO episodes, the lesser number of tropical depressions and typhoons tend to occur during warm episodes.

• In the northern part of Vietnam, there is no discernible impact of ENSO on the incidence of typhoon and tropical depressions.

• During the warm ENSO years, few but strong intensity typhoons and tropical depressions tend to occur earlier than usual (pre-typhoon season).

• Abnormal variations also noticed during non-ENSO years e.g. in 1966, there was no warm ENSO episode but there were less number of tropical depressions and typhoons. In 1960, 1978 and 1980, there were no cold ENSO, but there were large number of tropical depressions and typhoons.

The study on stream flows in respect of Yen Bai (Thau river), Ta Bu (Da river), Dua (Ca river), Nong Son (Thu Bon river), Cung Son (Ba river) stations revealed that the stream flow tend to be lower during warm ENSO and higher during cold ENSO. The magnitude of decrease of river runoff in El Nino years is different from year to year and from river to river. During La Nina year 1998, the runoff of all sample study rivers were lower than normal. The runoff of these rivers in the El Nino year 1997 is higher than long-term mean value. While the rivers of northern parts of Vietnam do not follow variations in consonance with ENSO, the rivers of central Vietnam tend to follow ENSO pattern.

Constraints of using climate forecast information

The above instances reveal the complexity of relationship between ENSO events and local climate variability. The development induced environmental degradation like reduction of forest cover, soil erosion, siltation, etc., which added complexity to local climate variability. Hence, micro-climate variations do not always follow the global ENSO pattern. These uncertainties post operational constraints for utilizing long-range forecast information for decision-making.

Opportunities for using climate forecast information

There is a need to undertake further research studies to establish the linkages or otherwise of local climate variabilities and ENSO indices to provide usable information to decision makers. Delineation of extreme climate event sensitive region based on past history could facilitate empirical measurement of potential effects of ECEs. The documentation of past history of ECE on various region and sectors would be useful to find out whether or not co-relation exists between climate variability related sector impacts and ENSO indices.  

top^

The Documentation Methodologies/ Approaches

The Workshop decided to undertake documentation by following three approaches, keeping in view limited availability of time and the resources available for documentation:

1. Time series data (1950-1998)

2. Natural disaster episode history documentation (1950-1998)

3. Case study of recent past ENSO episodes

Time Series Data

Three meteorological observation/ stream flow observation stations may be selected in each of the following nine agro-ecological zones to collect monthly rainfall, temperature, humidity, solar radiation, stream flow level data for the period 1950-1998:

• Northwest (Northwest of Bacbo)

• Northeast (Northeast of BacBo)

• North Midland zone

• Red River Delta

• North Central zone

• South Central zone

• Plateau of Trung-Trung-Bo

• Southeast zone

• Mekong Delta zone

The season-wise crop production data relating to rice, coffee and other secondary crops may be collected keeping in view the jurisdiction of the observation stations for the period 1950-1998.

Natural Hazard Incidence History

All the natural disaster episodes, which occurred in various parts of Vietnam from 1950-1998 could be documented covering the following essential features:

• Year of occurrence

• Season of occurrence

• Dates of occurrence

• Meteorological/ hydrological causes

• Names of affected provinces

• Details of impacts

• Institutional arrangements for response

• Details of response

Case study of distinct recent ENSO episodes

A qualitative assessment of the below-mentioned ENSO episodes may be undertaken to bring out the details of the impacts, the institutional arrangements to receive, process and apply climate forecast information, the type of intervention measures undertaken and the evaluation of the intervention measures.

El Nino

Case study of 1982-83
Case study of 1987-88
Case study of 1991-92
Case study of 1997-98

La Nina

Case study of 1984-85
Case study of 1988-89
Case study of 1995-96
Case study of 1998-99  

---

top^

Guidelines for Documentation

ADPC was requested to provide guidelines for documentation along with checklist for undertaking the documentation process.  

---

Outcomes of the Workshop

The various organizations/ agencies had agreed to undertake documentation process as per the framework presented below :

* As per the check list provided by ADPC  

---

top^

Implementation Plan

The Workshop resolved to constitute a working group to complete the documentation. The agreed implementation plan for completion of the documentation is as under :

Activity	Responsibility	Time Frame
Issue of communication to various Ministries/ Departments	Ministry of Agriculture and Rural Development - Department of Dyke Management and Flood & Storm Control - MARD	7.5.1999
First meeting of Working Group to finalize strategies for undertaking documentation with reference to guidelines for documentation prepared by ADPC.	Disaster Management Centre - Department of Dyke Management and Flood & Storm Control	20.5.1999
Completion of part I and part II of the documentation	All members of the Working Group	30.6.1999
2nd meeting of Working Group to review part I of the documentation	All members of the Working Group, ADP	10.7.1999
Completion of assessment reports	All members of the Working Group, ADP	15.7.1999
3rd meeting of the Working Group to review completion of part II of the documentation	All members of the Working Group, ADPC	30.7.1999
Review - documentation	ADPC	7.8.1999
4th meeting of the Working Group to complete the documentation in the light of review of ADPC	All members of the Working Group, ADPC	15.8.1999
Analysis and draft report preparation	All members of the Working Group, ADPC	15.9.1999
5th meeting of the Working Group to review the draft report of the documentation	All members of the Working Group, ADPC	1.10.1999
Presentation of the report at the country level Workshop	All members of the Working Group, ADPC	15.10.1999

top^

• Structure of the Workshop
• Summary of Discussions
• The Documentation Methodologies/ Approaches
• Guidelines for Documentation
• Outcomes of the Workshop
• Implementation Plan