Climate and Floods In Myanmar. Tin Yi (Assistant Director) DMH MYANMAR

Climate and Floods In Myanmar Tin Yi (Assistant Director) DMH MYANMAR

Lat 9 30 to 28 30 N, Long - 92 10 to 101 11 E Neighbouring countries India, Bangladesh, China, Laos, Thailand,

92 94 96 100 N INDIA CHINA Department of Meteorology and Hydrology ANDARMAN SEA THAILAND LAOS Meteorological Station- 63 Hydrological station - 30 Met & Hydro station - 39 Agro-Met Stations - 18 Aviation-Met station - 8 Seismological station - 11 100 50 0 50 100

Monsoon Onset in Northern Myanmar Areas During ( 1955-2008 ) 180 1977 175 168( 1992) 170 165(1977) 165 160 155 150 145 140 135 130 125 120 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Onset Days Nothern Onset Days NORMAL 5 per. Mov. Avg. (Nothern Onset Days) Yers - Climate change impact on onset criteria appreciable shift to late.since1977 to 2008 all year shown late advanced monsoon about 7 to 12 days later than normal.

ANNUAL MONSOON WITHDRAWAL DATES OF SOUTHERN MYANMAR DURING (1955-2008) 300 295 1989 y = -0.3615x + 291.89 290 285 280 275 283 276(1976) 270 265 260 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 withdrawal days 269(1991) Southern mean Linear (Southern) 264(2000) years - Monsoon withdrawal dates are shift to early. - Since1989 to 2008 (except 1993) all year shown early withdrawal monsoon about 15 to 25 days early than normal.

Duration of Monsoon since Onset in Northern till Withdrawl from Southern Myanmar Areas(1955-2008) 170 160 Nothern to Southen Mean 150 Linear (Nothern to Southen) 140 130 120 (1977)113 1989 130 110 100 90 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Duration(days) (1979)102 (2004)100 years -The duration of monsoon seasons were shorter than normal starting from 1989 - The late onset and the early withdrawal of monsoon are responsible for the shorter duration of monsoon seasons

14 12 10 8 6 4 2 0 Monsoon Depression in the Bay of Bengal During 1926-2008 y = -0.0813x + 9.293 1926 1928 1930 1932 2006 1934 1936 1938 1940 1942 1944 1946 1948 1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2008 frequency Linear (frequency) year frequency

ANNUAL MONSOON STRENGTH INDICES OF MYANMAR DURING 1951-2000 600 y = -0.1365x + 474.98 550 500 450 400 350 300 250 200 1950 1960 1970 Monsoon Indices Linear (Monsoon Indices) 5 per. Mov. Avg. (Monsoon Indices) 1980 1990 2000 2010 The years 1951, 1953,1957,1977,1979,1996 and 1998 were weak monsoon years, where the impact of EL Nino were evident in most years. YEARS

PERCENTAGE DEPARTURE OF ANNUAL AREA AVERAGE RAINFALLS OVER MYANMAR DURING THE PERIOD 1960-2000 PERCENTAE DEPARTURE 20 15 10 5 0-5 -10 1962 1970 1972 1973 1986 Percentage Departures Linear (Percentage Departures) 5 per. Mov. Avg. (Percentage Departures) 1993 1996 1999 1989 2000-15 -20-25 WETTER PHASE 1979 DRIER PHASE 1998-30 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 YEARS A phase change of decreasing in annual rainfall occurred starting from 1977 during the period 1960-2000.

ANNUAL PERCENTAGE DEPARTURES OF MONSOON RAINFALLS DURING 1947-2000 60 40 y = -0.7421x + 1456.1 20 PERCENTAE DEPARTURRES 0-20 -40-60 MEAN -80-100 Rainfall Departures Linear (Series1) 6 per. Mov. Avg. (Series1) -120 1940 1950 1960 1970 1980 1990 2000 2010 YEARS - The monsoon rainfall showed a continuous negative anomalies in each of every year from 1981 to 1998 except in 1990.

ANNUAL PERCENTAGE DEPARTURES OF TIM E AND AREA AVERAGED HEAT INDICES OF MYANMAR DURING THE PERIOD 1960-2000 6 4 COOLER PHASE WARMER PHASE DEPARTURES (% 2 0 MEAN -2-4 -6 1976 Heat Indices 5 per. Mov. Avg. (Heat Indices) Linear (Heat Indices) 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 YEARS Lwin.2001

ANNUAL DROUGHT INDICES OF MYANMAR DURING 1951-2000 40 y = 0.2582x - 507.97 30 20 DROUGHT INDEX 10 0-10 -20 Drought Index 5 per. Mov. Avg. (Drought Index) Linear (Drought Index) -30 1940 1950 1960 1970 1980 1990 2000 2010 YEARS The drought anomaly also showed positives anomalies in most years of 1980s and 1990s.

(1960-1969) Mean SSTA (2000-2008) Mean SSTA www.themegallery.com May -1st Dekad May -1 st Dekad

Severe Cyclonic Storms in Bay of Bengal(2006-2009) Severe Cyclonic Storm MALA, 24-30 April, 2006 Severe Cyclonic Storm AKASH, 2-15 May, 2007 - Global warming is forcing ocean temperatures to rise, which is causing storms, including cyclones and hurricanes, to intensify. - Higher ocean temperatures in the top couple of hundred feet of the ocean, which drives convection energy and moisture into these storms and makes them more powerful. Severe Cyclonic Storm NARGIS, 27 April 3 May, 2008 Cyclonic Storm AILA, 22-25 May, 2009 -Strong correlation between intense storms and global warming.

Climate change in Myanmar The annual onset dates of monsoon into Myanmar during 1955-2008 indicates that monsoon onsets were late starting from 1977. Starting from1989 ( except 1993), the withdrawal of monsoon from Myanmar were early than normal. The duration of monsoon seasons were shorter than normal starting from 1989 The late onset and the early withdrawal of monsoon are responsible for the shorter duration of monsoon seasons. The trend analysis of Monsoon depression (1926-2008)is the falling trend. The annual frequency of monsoon depressions becomes significantly less in 1980s and 1990s. After 2003, the frequency becomes more. The monsoon strength were weak in 1951, 1953,1957,1977,1979,1996 and 1998, where the impact of EL Nino were evident in most years. The normal monsoon breaks were disappeared in almost every years during 1989-1997. The break situation returned again in 1998, it however disappeared again from 1999 to 2006 and returned again in 2007 and 2008. The monsoon rainfall showed a continuous negative anomalies in each of every year from 1981 to 1998 except in 1990. The drought anomaly also showed positives anomalies in most years of 1980s and 1990s. Sea surface temperature rise, which is causing storms, including cyclones and hurricanes, to intensify.

Myanmar Average Annual Water Resources Potential by River Basin River Basin Number Name of the Principal River Basin Drainage Area (Thousand sq-km) Surface Water (Km 3 /annum) Ground water (Km 3 /annum) 1 Chindwin 115 141 58 2 Upper Ayeyarwady 193 228 93 3 Lower Ayeyarwady 96 86 153 4 Sittoung 48 81 28 5 Rakhine 58 139 42 6 Taninthayi 41 131 39 7 Thanlwin 158 258 75 8 Mekong 29 18 7 Total 738 1082 495

N River Forecasting Stations Ayeyarwady - 12 Stations Hkamti Myitkyina Homalin Katha Bhamo Chindwin - 5 Stations Thanlwin - 1 Station Sittoung - 2 Stations Shwegyin - 1 Station Bago - 1 Station Mawlaik Kalewa Monywa Hsipaw Sagaing Mandalay Myitnge Nyaung U Chauk Minbu Magway Aunglan Pyay Taungoo Henzada Madauk Shwegyin Zaungtu Bago Hpa-an Dokehtawady - 2 Station ANDARMAN SEA 100 50 0 50 100

Ayeyarwady and Chindwin - Intense heavy rain due to pronounced monsoon trough persisting for at least 3 days over Northern Myanmar areas - Heavy rainfall due to cyclonic storm crossing Myanmar and Bangladesh coasts during pre-monsoon and post-monsoon Sittaung and Thanlwin - Mostly due to rainfall associated with low pressure waves (the remnants of typhoons and tropical storms of South China Sea) moving from east to west across the country Small rivers channels Streams in mountainous regions - Coastal Floods (Storm Surges) - Small River Floods (Flash Floods)

Severe Flood Years (Since 1966 ) River Highest Water Level Recorded at Year Total Stations above Danger Level Chindwin Homalin 1968 14 stations Ayeyarwady Chauk, Minbu, Aunglan, Pyay 1974 20 stations Chindwin Mawlaik 1976 18 stations Ayeyarwady Myitkyina, Katha 1979 14 stations Chindwin Hkamti 1991 16 stations Sittoung Shwegyin Chindwin Thanlwin Ayeyarwady Madauk Shwegyin Kalewa, Monywa Hpa-an Bhamo, Sagaing, Mandalay, Nyaung Oo, Magway 1997 19 stations 2002 15 stations 2004 21 stations

Flood Record in Myanmar (since 1966) Stations DangerLevel (cm) Max. WL (cm) Flood Duration above DL (m) Year Ayeyarwady Myitkyina 1200 1411 4 days 12 Hrs 2.11 1979 Bhamo 1150 1338 8 days 2 Hrs 2.38 2004 Katha 1040 1154 7 days 6 Hrs 1.14 1979 Mandalay 1260 1382 16 Days 1.22 2004 Sagaing 1150 1274 17 Days 6 Hrs 1.24 2004 Nyaung Oo 2120 2263 16 Days 12 Hrs 1.43 2004 Chauk 1450 1532 12 Days 12 Hrs 0.82 1974 Minbu 1700 1982 17 Days 12 Hrs 2.82 1974 Aunglan 2550 2737 15 Days 1.87 1974 Pyay 2900 3025 13 Days 1.25 1974 Hinthada 1342 1582 23 Days 12 Hrs 2.40 1966 Chindwin Hkamti 1360 1771 18 Days 6 Hrs 4.11 1991 Homalin 2900 3107 18 Days 6 Hrs 2.07 1968 Mawlaik 1230 1608 15 Days 12 Hrs 3.78 1976 Kalewa 1550 1920 10 Day 12 Hrs 3.70 2002 Monywa 1000 1099 9 Days 6 Hrs 0.99 2002

Stations Flood Record in Myanmar (since 1966) DangerLevel (cm) Max. WL (cm) Flood Duration above DL (m) Year Sittoung Toungoo 600 725 16 Days 18 Hrs 1.25 1973 Madauk 1070 1244 31 Days 1.74 1997 Dokhtawady Hsipaw 600 618 12 Hrs 0.18 1971 Myitnge 870 1048 8 Days 6 Hrs 1.78 2006 Shwegyin Shwegyin 700 927 4 Days 12 Hrs 2.27 1997 Bago Bago 910 950 2 Days 6 Hrs 0.4 1995 Thanlwin Hpaan 750 936 38 Days 1.86 2002

Percentage of Occurrence of Floods in Months and Flood Frequency along Ayeyarwady River Stations Monthly Flood Frequency(%) June July August Sept Oct Period Flood Frequency Flood Year Myitkyina 1(14%) 5(57%) 0 1(15%) 1(14%) 1966-08 7 in 43 yrs 7 in 43 yrs Bhamo 1(6%) 11(60%) 2(11%) 3(17%) 1(16%) 1968-08 18 in 41 yrs 13 in 41 yrs Katha 3(8%) 21(62%) 6(18%) 2(6%) 2(6%) 1966-08 34 in 43 yrs 22 in 43 yrs Mandalay 0 5(63%) 0 1(12%) 2(25%) 1976-08 8 in 33 yrs 6 in 33 yrs Sagaing 0 7(28%) 8(32%) 7(28%) 3(12%) 1966-08 25 in 43 yrs 20 in 43 yrs Nyaung Oo 0 14(33%) 13(31%) 10(24%) 5(12%) 1966-08 42 in 43 yrs 29 in 43 yrs Chauk 0 3(34%) 3(33%) 2(22%) 1(11%) 1973-08 9 in 36 yrs 9 in 36 yrs Minbu 0 9(24%) 15(38%) 11(28%) 4(10%) 1966-08 39 in 43 yrs 26 in 43 yrs Magway 0 7(37%) 5(26%) 5((26%) 2(11%) 1990-08 19 in 19 yrs 10 in 19 yrs Aunglan 0 3(21%) 5(36%) 6(43%) 0 1973-08 14 in 36 yrs 11 in 36 yrs Pyay 0 5(29%) 4(24%) 7(41%) 1(6%) 1966-08 17 in 43 yrs 15 in 43 yrs Hinthada 0 12(25%) 21(44%) 12(25%) 3(6%) 1967-08 48 in 42 yrs 26 in 42 yrs

Percentage of Occurrence of Floods in Months and Flood Frequency along Chindwin and other Rivers Stations Monthly Flood Frequency(%) June July August Sept Oct Chindwin River Period Flood Frequency Flood Year Hkamti 3(7%) 26(57%) 12(26%) 5(10%) 0 1967-08 46 in 42 yrs 29 in 42 yrs Homalin 4(7%) 28(50%) 15(27%) 7(13%) 2(3%) 1968-08 56 in 41 yrs 32 in 41 yrs Mawlaik 1(2%) 23(40%) 17(30%) 11(9%) 5(9%) 1965-08 57 in 44 yrs 32 in 44 yrs Kalewa 1(2%) 23(40%) 17(30%) 12(21%) 4(7%) 1966-08 57 in 43 yrs 33 in 43 yrs Monywa 0 16(38%) 14(34%) 9(21%) 3(7%) 1966-08 42 in 43 yrs 29 in 43 yrs Dokehtawady River Myitnge 1(2%) 15(25%) 19(32%) 17(29%) 7(12%) 1972-08 59 in 37 yrs 31 in 37 yrs Sittoung River Toungoo 0 9(14%) 37(59%) 12(19%) 5(8%) 1966-08 63 in 43 yrs 34 in 43 yrs Madauk 2(2%) 23(27%) 50(58%) 10(11%) 2(2%) 1966-08 87 in 43 yrs 40 in 43 yrs Shwegyin River Shwegyin 2(5%) 9(23%) 27(69%) 1(3%) 0 1965-08 39 in 44 yrs 24 in 44 yrs Bago River Bago 1(6%) 5(31%) 10(63%) 0 0 1965-08 16 in 44 yrs 13 in 44 yrs Thanlwin River Hpaan 2(2%) 33(36%) 45(49%) 11(12%) 1(1%) 1966-08 92 in 43 yrs 38 in 43 yrs

Annual Flood Occurrence Percentage in Myanmar (1966-2008) 100 90 80 70 60 50 40 30 20 10 0 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 year More than 50 % - 23 yrs Equal to 50 % - 3 yrs Less than 50 % - 17 yrs Annual Flood Occurrence %

1600 1400 1200 1000 800 Annual Maximum Water Levels at Myitkyina Station (Ayeyarwady)(1972-2008) 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2400 2200 2000 1800 Year Annual Maximum Water Levels at Nyaung U Station (Ayeyarwady)(1972-2008) Water Level (cm) 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 Year 1600 1400 1200 Annual Maximum Water Levels at Hinthada Station (Ayeyarwady)(1966-2008) Water Level (cm) 1967 2003 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000 2006 1200 1000 800 Annual Maximum Water Levels at Katha Station (Ayeyarwady)(1966-2008) Year Water Level (cm) 1966 2002 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2005 2008 Year Water Level (cm)

1700 1500 1300 1100 900 Annual Maximum Water Levels at Hkamti Station (Chindwin)(1967-2008) 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000 2003 2006 Year 1600 1400 1200 1000 800 Annual Maximum Water Levels at Mawlaik Station (Chindwin)(1965-2008) Water Level (cm) 1965 2004 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2007 Year Water Level (cm) 1200 1000 800 Annual Maximum Water Levels at Monywa Station (Chindwin)(1965-2008) 1966 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 2008 Year 1200 1000 800 600 Annual Maximum Water Levels at Myitnge Station (Dokehtawady)(1972-2008) Water Level (cm ) 1972 2004 2006 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2008 Year Water Level (cm)

1300 1100 900 700 Annual Maximum Water Levels at Madauk Station (Sittoung)(1966-2008) 1966 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 2008 Year 1000 800 600 400 Annual Maximum Water Levels at Shwegyin Station (Shwegyin)(1965-2008) Water Level (cm) 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 Year Water Level (cm) 1000 900 800 700 600 500 Annual Maximum Water Levels at Hpa-an Station (Thanlwin)(1965-2008) 1966 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 2008 Year 1000 950 900 850 800 Annual Maximum Water Levels at Bago Station (Bago)(1965-2008) Water Level (cm) 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 Year Water Level (cm)

Conclusion Impacts of climate change also occur in Myanmar DMH is only one service issuing warnings for hydrological, Meteorological and seismological disasters. The relevant depts. in Myanmar are implementing the projects, workshops and meetings related to the climate change, also climate change assessment and adaptation cooperating with international organizations. DMH is also doing the analysis of the climate change trends and also develop the scenario for climate data. DMH is very actively contributing in the projects, workshops and meetings related with climate change assessment and adaptation.