Climate change adaption in VN

Workshop on
AAAAAAAAAAAAAAAA

CLIMATE CHANGE ADAPTION
IN VIETNAM
Tran Hong Thai,
Deputy Director, Vietnam Institute of Meteorology, Hydrology and Environment


New Zealand, December 2013


CONTENTS
1)

Climate Change in Viet Nam

2)

Climate Change Scenarios

3)

Vietnam Response to Climate Change


CURRENT STATUS OF
CLIMATE CHANGE IN VIETNAM


Most likely and serious Impacts

 3,000 km
coast line

 Sea level
rises as
the key
impact

4


WB report - Problem from CC in Viet Nam





Sea level rises 20 cm in the last 50 years
500 dead per year
US$ 1.5 billion (1,5% of annual GDP)
80% farmers living in rural areas with agriculture
livelihood
 Threats for millennium objectives, sustainable
development and poverty reduction
 The poor suffer twice
 Vietnam is the second biggest rice exporter

5

Mean temperature
Temperature

Rainfall

Lạnh hơn

Ấm hơn

°C/thập kỷ

Trend of mean annual
temperature

 Over the past 50 years,
annual average temperature
has increased 0.5oC.
 Winter temp increased
faster than summer temp.
 Temp in the North
increased faster than in the
South.
 Temp inland increased
faster than in coastal areas
and islands.


Rainfall
Rainfall

drier

wetter

%/thập kỷ

• Dry season: slight change in
the North, but increasing
strongly in South;
• Rainy season: decreases ~ 510% in the North, increase ~
5-20% in the South;
• Annual mean: increase in the
South, decreases in the North;
• Rainfall in rainy season in
Central VN increases stronger
than
others,
up
to
~20%/50years;

Change in rainfall (%) over 50 past years


Trend of maximum and minimum daily
Temperature
Tn trend

Tx trend
24N

Tx

NE
22N

24N

NW

deg.C/decade

ND
20N

Tn

NE
22N

0.55

NC

NW

20N

0.35

0.55

NC

0.45

18N

deg.C/decade

ND

0.45
0.35

18N

0.25

0.25
0.15

16N

0.15

16N

0.05

0.05

SC
14N

−0.05

CH

SC
14N

−0.15
−0.25

12N

−0.05

CH

−0.15
−0.25

12N

−0.35

−0.35
−0.45

10N

8N
102E

S

104E

106E

−0.45

10N

S

−0.55

108E

110E

112E

8N
102E

104E

106E

−0.55

108E

110E

112E

• Minimum temperature has increased more than maximum
temperature, particularly over NW, south of NC, SC and CH


Extreme rainfall amount
RX1day trend

RX5day trend

24N

NE

NE
22N

NW

%/decade

ND
20N

11

NC

NW

20N

7

11

NC

9

18N

%/decade

ND

9
7

18N

5
3

16N

5
3

16N

1

SC
14N

−1

CH

1

SC
14N

−5

12N

−1

CH

−3

−3
−5

12N

−7
−9

10N

8N
102E

S

104E

106E

−7
−9

10N

S

−11

108E

110E

112E

8N
102E

104E

106E

−11

108E

110E

Khô hơn

22N

Ẩm ướt hơn

24N

112E

RX1day: annual maximum 1-day rainfall (mm)
RX5day: annual maximum consecutive 5-day rainfall (mm)

• Have not change significantly for NW, NE, NC, and most stations of S.
• Significantly decrease at some stations in ND by up to 11%/decade
• Significantly increase at most stations in SC and CH


Typhoon
• Slight increase in east
sea, but change in
frequency of typhoon
landing Vietnam is not
clear;
• Landing area of typhoon
retreated southward;;
• frequency of very strong typhoon
(> level 12) increases;
• Typhoon season withdraw tends
to be lately;
•


Drought
Drought occure more requently,
especially extreme levels

Dry and deficient water was

significantly in dry season of 20102011. Water level, discharge, and water
reserves in water reservoir have
minimum levels.


Flood
 Red River: Annual flow has decreased in recent years, but
strong flood events occure more requently.
 Mekong River: Sequence of strong flood occurred in
2000, 2001 and 2002, crest of flood at Tan Chau is over
4,5m indicate that there is increase of hydrological
extremes.
 More and more flash flood is serious, number of serious
flash flood in period:
• 1970 - 1980: 7;
• 1981 - 1990: 8;
• 1991 - 2000: 103;
• 2001 - 2013: 183.
20
18

Số lần xuất hiện

16
14
12

10

8

6
4
2
0


History Floods

Lao Cai 2012

Đập Khe Mơ – Hà Tĩnh

Quảng Ngãi 11/2010


Others extreme Climatic Events, Disaster
• Drizzling rain decreases
significantly;
• Cold front decreases;
• Cold days, damaging cold
days decrease, but appeared
extremes cold spell;
• Heat wave increases in central
and southern areas;
• Off-season extreme rainfall
events occure more requently;
• ENSO has stronger effects on
weather and climate in Viet
Nam

Climate Change Scenarios
for Viet Nam


Climate Change Scenarios
Emission Scenarios
Models Applied
• Statistical Downscaling:
• Low emission scenario (B1);
• Medium emission scenario (B2) SDSM, SimClim
• High emission scenario (A2,
• Dynamic Downscaling:
A1FI)
AGCM/MRI, PRECIS
Baseline: 1980-1999

GHG emission scenario (IPCC)


Climate Change Scenarios
•
•
•
•

Temperature in Winter: XII-II
• Yearly Average Temperature
Temperature in Spring: III-V
• Extreme Temperature in Winter

Temperature in Summer: VI-VII • Extreme Temperature in Summer
Temperature in Autumn: IX-XI
• Annual Extreme Temperature
Number of Days with Temperature > 35oC

Mức tăng nhiệt độ mùa đông
kịch bản phát thải thấp

Mức tăng nhiệt độ mùa đông
kịch bản phát thải trung bình

Mức tăng nhiệt độ mùa đông
kịch bản phát thải cao


Climate Change Scenarios
•
•
•
•

Rainfall in Winter: XII-II
Rainfall in Spring: III-V
Rainfall in Summer: VI-VII
Rainfall in Autumn: IX-XI

(a)

(b)

• Annual Rainfall
• Maximum Daily Rainfall

(c)


Sea Level Rise Scenarios

• Low emission scenario (B1): 49-64cm.
• Average emission scenario (B2): 57-73cm.
• High emission scenario (A1FI): 78-95cm.


Inundation Map
(Sea Level Rise 1m)
Area: 20.876 Km2 (6,3%)
If sea level rise 1 m:
• 39% area of Mekong Delta, over 10%
area of Red River Delta, over 2,5% of
coastal area of the Central, over 20%
area of Ho Chi Minh city will be
inundated.
• 35% population of Mekong Delta, over
9% population of Red River delta,
about 9% population of the Central,
7% population of HCM City are
directly affected.
• 4% of the railway system, 9% of
national highways, 12% of provincial
highways unaffected.

Red River Delta

Tỉnh
Q Ninh
Ha Noi
Ha Nam
Hai Phong
Hung Yen
Hai Duong
Bac Ninh
Ninh Binh
Thai Binh
Nam Dinh
Vinh Phuc

%
11.3
0.3
6.0
17.4
3.3
7.2
1.6
10.2
31.2
24.4
0.0

TP HỒ CHÍ MINH
20.1 %


Mekong Delta
39%

AnGiang
BacLieu
BenTre
CaMau
CanTho
DongThap
VinhLong
TraVinh
SocTrang
TienGiang
LongAn
KienGiang
HauGiang

2.2%
45.7%
33.3%
55.9%
19.0%
4.8%
15.6%
27.8%

51.2%
30.3%
28.5%
74.8%
79.4%


Case study of
Kiên Giang and Cà Mau


Approach
 The study area includes 2
provinces: Kiên Giang and
Cà Mau, it is a part of Cuu
Long Delta.
 To assess impacts of
Climate change on Water
resources of the two
provinces it is necessary to
assess the impacts on the
whole Cuu Long Delta.
 The boundaries are: from
Kratie and Great lake to
the sea.

Kratie