National Climate and Water Briefing - Bureau of Meteorology · 2017-08-02 · Sea ice •Antarctic...

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Transcript of National Climate and Water Briefing - Bureau of Meteorology · 2017-08-02 · Sea ice •Antarctic...

27 July 2017

National Climate and Water Briefing

Photo: Dion Georgopoulos Source: CanberraTimes.com.au 24 July 2017

Image: Jan Kratochvila

Welcome

Graham Hawke Group Executive Bureau of Meteorology

Photo: Matt Bastin

Climate conditions and outlook Joel Lisonbee Senior Climatologist Bureau of Meteorology

Watsonia, Victoria | 25 July 2017 Photo: Catherine Ganter

Recent conditions

• Recent conditions • State of climate drivers • Climate outlook

El Niño

La Nina Negative IOD

Positive IOD

Negative IOD and neutral ENSO

Latest weekly values (23 July) • NINO3.4: +0.35 °C • IOD: –0.15 °C

EN

SO

– N

INO

3.4

(°C

)

IOD

inde

x (°

C)

-1.6

-1.2

-0.8

-0.4

0

0.4

0.8

1.2

1.6

-3.2

-2.4

-1.6

-0.8

0

0.8

1.6

2.4

3.2

Financial year overview: temperatures

Maximum temperature July 2016 – June 2017

Minimum temperature July 2016 – June 2017

December 2016 – February 2017: heatwaves

Highest daily maximum temperature for February 2017

• Waves of heat: • 22–31 December • 10–15 January • 17–21 January • 9–12 February

• Most severe heatwave for

New South Wales since 1939

Sir Ivan Fire 14 February 2017

• Pyro-cumulonimbus and wind change

Financial year overview: rainfall

12 month rainfall July 2016 – June 2017

July–September 2016

October–December 2016

January–March 2017

April–June 2017

September 2016: floods South Australia, Victoria, Tasmania, New South Wales and Queensland

Riverine flooding, September 2016 Forbes, New South Wales 20–25 September 2016

• Perth rainfall, 9 February:

• 114.4 mm

• Perth's second-wettest day on record

• More than January, February and March averages combined

• Wettest summer ever recorded (141 years of record)

Rainfall anomalies: February 2017

February: floods southwest Western Australia

400 mm

200 mm

100 mm

50 mm

25 mm

10 mm

0 mm

-10 mm

-25 mm

-50 mm

-100 mm

-200 mm

-400 mm

Phillips River bridge, southwest Western Australia Photo: Dana Fairhead

March: rainfall Tropical cyclone Debbie accumulated rainfall

Tropical cyclone Tropical

cyclone

300 mm 100 60 55 50 45 40 35 30 25 20 15 10 9 8 7 6 5 4 3 2 1 0.5 0.2 0.1 0

March rainfall

Wholesale price index for Gourmet Tomatoes, Melbourne 2015–16 and 2016–17

June: rainfall • Australia

• 2nd lowest June rainfall on record • Lowest since 1940

• Victoria

• Lowest June rainfall on record • Previous lowest in June 1944

• Murray-Darling Basin

• 4th lowest June rainfall on record • Lowest since 1986

Winter-to-date: rainfall

• Western Australia • On track for 2nd lowest June–July

period on record • Victoria

• On track for driest June–July on record

• more than 50% below average

As at 25 July

June: minimum temperatures

• Australia • 0.4 °C below average

• South Australia

• 7th lowest minimums on record • 1.7 °C below average • Coolest June since 2007

Winter-to-date: minimum temperatures

• Series of cold nights in the south

continued from June into July

• July minimum temperatures on track to be the lowest since at least 2002 for • Victoria • New South Wales and • Tasmania

As at 25 July

June maximum temperatures

• Australia • 7th highest June maximums

• Western Australia

• 3rd highest June maximums

• Murray-Darling basin • 8th highest June maximums

Winter-to-date maximum temperatures

• Australia • Likely to be warmest June–July

period on record

• All states apart from Victoria and Tasmania are likely to have one of their top ten warmest Julys on record for maximum temperature

As at 25 July

More warm days to come…

• A 'warm wave' is forecast for coming week

• Record July daytime temperatures predicted across almost all of Australia

Experimental product

Global temperatures: 2017

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Diff

eren

ce fr

om 2

0th

cent

ury

aver

age

(°C

)

Global temperature accumulated monthly anomalies

1998

2005

2009

2010

2013

2014

2015

2016

2017

2016

2017

2015

Data: NOAA NCDC

International climate events

African famine European heatwave

Cold snap in South America

New Zealand flooding

Northern hemisphere tropical cyclones

• Third consecutive failed wet season for east Africa

• Severe famine in Ethiopia

• Wildfires in Portugal, Spain, Italy, Sicily and Greece

• London, hottest June Day since 1976

• Rare snowfall in Santiago as 'Chile turns chilly' in mid-July

• State of emergency declared in South Island cities of Otago, Christchurch, Timaru and Dunedin

• More than 200 mm in 24 hours to 22 July

• 8 active tropical storms on 24 July

• 6 named • Typhoon Noru, strongest

storm of the season so far

Sea ice

• Antarctic sea-ice at record low • 12 July: Larson C ice-shelf

breaks • 13 July: US National Ice

Center issues press release confirming the new iceberg and officially naming it A-68

• Arctic sea-ice low, but not record

• Record low sea ice extent is from 2012

Larsen C Ice Shelf

Iceberg A-68

False-color image captured by NASA's Landsat’s Thermal Infrared Sensor

NASA: Visible Infrared Imaging Radiometer Suite (VIIRS)

Climate drivers

• Recent conditions • State of climate drivers • Climate outlook

What's driving our climate?

• The usual suspects – Oceanic Drivers Indian Ocean Dipole El Niño–Southern Oscillation

– Atmospheric Drivers Southern Annular Mode Subtropical ridge Madden–Julian Oscillation

What's driving our climate?

Oceanic climate drivers Weekly sea surface temperature anomalies: Week ending 23 July 2017

Latest weekly values (23 July) • NINO3.4: +0.35 °C • IOD: -0.15 °C

Southern Annular Mode (SAM) index observations and forecast

Southern Annular Mode

• Currently neutral • Mostly positive since May • Model guidance shows wide

spread in possibilities

Positive SAM winter rainfall impacts

Subtropical Ridge June 2017 Mean Sea Level Pressure (MSLP)

June 2017 MSLP anomaly • High pressure over southern Australia through June

• Contributed to: • high daytime and low

overnight temperatures • low rainfall

Madden–Julian Oscillation (MJO)

0

0.5

1

1.5

2

2.5

MJO amplitude last 60 days

Weak or indiscernible

Moderate

Strong • Only an influence when moderate

to strong • Different impacts based on location

and time of year • Has been mostly weak for past month • Forecast to remain weak for next

three weeks

Week 1 Week 2–3 Week 4–5

Climate outlooks

• Recent conditions • State of climate drivers • Climate outlooks

El Niño–Southern Oscillation outlook: July

-2

-1.6

-1.2

-0.8

-0.4

0

0.4

0.8

1.2

1.6

2

observed

BOM

Canada

ECMWF

Japan

Meteofrance

NASA

NOAA

UKMO

NINO3.4 outlook

° C

OISSTv2 (1981-2010)

Dec Nov Oct Sep Aug Jul

Jun May Apr Mar Feb Jan

High skill Mod skill Low skill

0 1 2 3 4 5 6 7 8

Out

look

sta

rt m

onth

Lead time, months

High skill

Low skill

Low to moderate skill

August–October rainfall outlook

Chance of exceeding median rainfall, August–October 2017

August

September

Past Accuracy

Past Accuracy

Past Accuracy

August–October maximum temperature outlook

Chance of exceeding median maximum temperature, August–October 2017

August

September

Past Accuracy

Past Accuracy

Past Accuracy

August–October minimum temperature outlook

Chance of exceeding median minimum temperature, August–October 2017

August

September

Past Accuracy

Past Accuracy

Past Accuracy

Introducing mid-month Climate Outlooks

• First look: – Will usually be issued 2nd Thursday of month – Integrates early intelligence from models – Short video

• End-of-month: – Clearest picture – Issued closest to start of outlook period – Up-to-date summary of current climate

influences – Comprehensive video including wrap-up of

recent conditions

June bushfires and northern bushfire outlook

Northern rainfall onset outlook • Onset occurs when the rainfall total in a

particular region reaches 50 mm

Average date of onset (accumulation of 50 mm)

This year, odds favour early onset over northern Queensland and the Kimberley coast

Summary

• In contrast to last year, winter 2017 (so far): – Dominated by high pressure – Among driest on record – Warm days; cold at night for the southeast

• Most large-scale climate drivers are currently neutral • Outlooks

– Above-median temperatures likely for next three months – Below-median rainfall expected for southern and western Australia

Thank you

Questions Joel Lisonbee

Birchip, Victoria | 6 July 2017 Photo: Catherine Ganter

Hydrological conditions and outlook Aaron Wassing Project Manager, National Water Account

Ord river Farming and crops at Kununurra Photo: John Carnemolla

Recent hydrological conditions

• Recent hydrological conditions • Water storages • Past water use and sources • Streamflow outlooks

Rainfall

May 2017 June 2017 July 2017 to-date

As at 21 July

Effective rainfall

May 2017 totals June 2017 totals

Effective rainfall—southern Australia Comparing June for 6 years

June 2015 June 2016 June 2017

June 2013 June 2014 June 2012

Effective rainfall

May 2017 totals June 2017 totals July 2017 totals to date

As at 21 July

Soil moisture (10–100 cm)

May 2017 June 2017 July 2017 to-date

As at 21 July

Streamflow observations June 2017

April 2017

• High flow at 46 locations (14%)

• Near-median flow at 67 locations (21%)

• Low flow at 189 locations (59%)

Streamflow observations Murray–Darling Basin

Water storages

• Recent hydrological conditions • Water storages • Past water use and sources • Streamflow outlooks

Water storage levels

Murray–Darling Basin storages

Past water use and sources

• Recent hydrological conditions • Water storages • Past water use and sources • Streamflow outlooks

National Water Account

• 2015–16 is 7th annual account

• 10 regions

• 75% of population

• More than 80% of national water use

Water sources and use: 2015–16

Trends in urban regions

Murray–Darling Basin water use and availability

Storages Water use

Murray–Darling Basin water use and availability

Storages Water use

Murray–Darling Basin water use and availability

Storages Water use

Murray–Darling Basin water use and availability

Storages Water use

Murray–Darling Basin water use and availability

Storages Water use

Murray–Darling Basin water use and availability

Storages Water use

Streamflow outlooks

• Recent hydrological conditions • Water storages • Past water use and sources • Streamflow outlooks

Streamflow forecasts July–September 2017

• High flow at 56 locations (18%)

• Near-median flow at 100 locations (31%)

• Low flow at 162 locations (51%)

• Low to moderate forecast skill mainly in southern Australia; high skill in north

Summary

• Dry conditions across southern Australia in June (typically a wet month) • Low observed streamflows in June

– 59% of all sites – almost 80% across Murray–Darling Basin

• Water storage levels continue to fall across much of southern Australia • Continued low streamflows forecast for July–September at half of sites, particularly in

southern Australia

Thank you Questions?

Wivenhoe Dam, QLD Photo: Alecia Scott

Aaron Wassing

Next briefing

Thursday, 31 August 2017

Melbourne, Victoria | 18 June 2017 Photo: Vanessa Webb