Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
National Climate and Water Briefing Wheat silos Mintaro South Australia
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Welcome
Dr Rob Vertessy Director
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Climate conditions and outlook
Joel Lisonbee Senior Climate Liaison Officer
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Recent conditions • Recent conditions
• Climate influences
• Rainfall and temperature outlooks
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• Event totals (3 days to 9am this morning)
• 478 mm at Beaumont (Kangaroo Valley)
• 413 mm at Nowra
• 200 mm+ at Wollongong to Narooma received
• Moderate flooding for the Shoalhaven river and Sussex inlet.
• Warragamba Dam spilt this morning, first time since 2012.
NSW weekly rainfall total, ending 26th August.
NSW East Coast Low
400 mm 300 mm 200 mm 150 mm 100 mm 50 mm 25 mm 15 mm 10 mm 5 mm 1 mm
Satellite imagery
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• Two significant cold outbreaks in southeast
• Heatwave in north
• Nationally, Australian temperatures were 0.4 °C above average
Temperature
July 2015
Maximum temperature deciles Minimum temperature deciles
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Rainfall deciles, May–July 2015
Rainfall
Rainfall deciles, July 2015
July
• Australian rainfall 31% below average
• All States and Territories below average
May–July
• Australian rainfall 19% below average
• Southwest Western Australia 2nd lowest on record
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Rainfall deficiencies
July 2014 – July 2015 October 2012 – July 2015
Update on wed to include southeast nsw rain
Percentage of average August rainfall 1–26 August 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Climate influences • Recent conditions
• Climate influences
• Rainfall and temperature outlooks
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
El Niño Sea surface temperature
July 2015
NINO3.4 recent anomalies • July: +1.5 ⁰C
• Latest weekly: +1.9 ⁰C (to 23rd August)
NINO3.4
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
El Niño Sub-surface and
atmosphere
Southern Oscillation Index Pacific Ocean sub-surface temperatures
May
June
July
August
Cloud patterns Three months to 22 August 2015
More cloud Less cloud than normal than normal
30-day moving SOI January 2013 – August 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• Develop in late autumn–winter
• Peak at end of year
• Dissipate in autumn
Of 26 El Niños in past 100 years:
• 50% have transitioned to Neutral
• 40% have transitioned to La Niña
• 10% followed by El Niño
Ten El Niño events since 1980
El Niño evolution
-3.2
-2.4
-1.6
-0.8
0
0.8
1.6
2.4
3.2
Jan
Feb
Mar
Apr
May Jun
Jul
Aug
Sep Oct
Nov
Dec Jan
Feb
Mar
Apr
May Jun
Jul
Aug
Sep Oct
Nov
Dec
year1 year2
1982-831987-881991-921993-941994-951997-982002-032006-072015-16
NIN
O3.
4 (°
C)
-3.2
-2.4
-1.6
-0.8
0
0.8
1.6
2.4
3.2
Jan
Feb
Mar
Apr
May Jun
Jul
Aug
Sep Oct
Nov
Dec Jan
Feb
Mar
Apr
May Jun
Jul
Aug
Sep Oct
Nov
Dec
year1 year2
1982-831987-881991-921993-941994-951997-982002-032006-072009-102015-16
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
NINO3.4 forecasts from eight international climate models
El Niño Model outlook
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
El Niño Global impacts
• Papua New Guinea drought and frosts
• Record typhoon season in north Pacific
• Weaker than usual Indian Monsoon after strong start
• Very wet in Argentina, Paraguay and southern Brazil
Can build on this one
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
El Niño Global impacts
Record global temperatures
• Hottest July
• Hottest month
• Hottest year-to-date
• Hottest 12-months
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• Indian Ocean Dipole currently neutral
• Warmer than average waters across Indian Ocean Basin
Sea surface temperature anomalies, week ending 23 August 2015
2015
Data: ERSST v4 1981–2010 base period 0–40°S 30–120°E
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1950
1953
1956
1959
1962
1965
1968
1971
1974
1977
1980
1983
1986
1989
1992
1995
1998
2001
2004
2007
2010
2013
July temperature anomalies Southern Indian Ocean
1997
2015
1982
Indian Ocean
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• Indian Ocean Dipole currently neutral
• Warmer than average waters across Indian Ocean Basin
Sea surface temperature anomalies, week ending 23 August 2015
2015
Indian Ocean Dipole Model outlook
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Recent conditions • Recent conditions
• Climate influences
• Rainfall and temperature outlooks
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Rainfall outlook
Spring 2015
Chance of exceeding median rainfall September–November
Chance of exceeding median rainfall September
Chance of exceeding median rainfall October
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Rainfall outlook
Spring 2015
Chance of exceeding median rainfall September–November
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Temperature outlook
Spring 2015
Chance of exceeding median maximum temperature September–November
Chance of exceeding median minimum temperature September–November
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Northern rainfall onset outlook
Chance of early northern rainfall onset in 2015
Average date of northern rainfall onset (1960–2009)
Normal onset:
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
In summary
• El Niño is dominant climate driver globally
• Strong El Niño does not always mean strong rainfall impact
• West likely to be wetter than usual
• Extended frost risk period
• Northern rainfall onset likely to be later than normal in north and earlier in central parts
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Thank you
Questions?
Joel Lisonbee Senior Climate Liaison Officer
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Hydrologic conditions and outlook
Dr Christopher Pickett-Heaps Hydrologist, Seasonal Streamflow Forecasting Brindabellas, ACT (C. Pickett-Heaps)
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Hydrologic conditions and outlook
• Recent hydrologic conditions
• Water storages
• Streamflow outlook
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Rainfall deciles Effective rainfall
Recent conditions
July 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Upper-layer soil moisture 1-month change in upper-layer soil moisture
Recent conditions
July 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Lower-layer soil moisture 12-month change in lower-layer soil moisture 1-month change in lower-layer soil moisture
Recent conditions
July 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Observed streamflow
July 2015
• High flow at 23 locations
• Near median flow at 67 locations
• Low flow at 103 locations
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
May 2015 June 2015 July 2015
Observed streamflow
Southeast Australia
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Observed streamflow trend
PR
OP
OR
TIO
N O
F S
ITE
S (%
) AC
RO
SS
AU
STR
ALI
A
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Serpentine Reservoir, Western Australia
Hawkesbury – Island Hill, NSW
Cumulative streamflows
CU
MU
LATI
VE
FLO
W (G
L)
CU
MU
LATI
VE
FLO
W (G
L)
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Cumulative streamflows
CU
MU
LATI
VE
FLO
W (G
L)
Total inflows Melbourne Water
Thomson O’Shannassy Upper Yarra Maroondah
CU
MU
LATI
VE
FLO
W (G
L)
Total inflows southern Murray–Darling Basin
Dartmouth Hume Eildon Goulburn Weir
El Niño progression?
August 2015 streamflow forecast
1997 and 1982 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Hydrologic conditions and outlook
• Recent hydrologic conditions
• Water storages
• Streamflow outlook
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Water storages
As at 20 August 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Water storage levels
Change from last year
20 August 2015 20 March 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Hydrologic conditions and outlook
• Recent hydrologic conditions
• Water storages
• Streamflow outlook
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
• High flow at 17 locations
• Near median flow at 56 locations
• Low flow at 122 locations
• Generally moderate to high forecast skill
Forecast skill Most likely forecast outcome
Streamflow outlook
August–October 2015
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
In summary • Low observed streamflows for July 2015
• Below-average lower-layer soil moisture in western Victoria and southwest Western Australia
• Below-average cumulative streamflows for major storages in southeastern Australia
• Low streamflows likely in August–October for majority of locations across southern Australia
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Thank you
Questions?
Dr Christopher Pickett-Heaps Hydrologist, Seasonal Streamflow Forecasting
Bureau of Meteorology www.bom.gov.au National Climate and Water Briefing 27 August 2015
Next briefing
24 September 2015
Top Related