A severe dust event overthe Mongolian Gobi in 3-5 March, 2016
Dr.D.Jugder and E.Munkhjargal
Information and Research Institute ofMeteorology, Hydrology and Environment
The 4th Session of East Asia winter Climate OutlookForum, (EASCOF-IV)
Ulaanbaatar, 8-9 November, 2016

Presentation contents• Introduction• Characteristics of the severe dust event– Land surface condition for dust emission– Weather condition for the dust event– Observed wind, PM10 and visibility– Vertical extend of dust by lidars– Spatial distribution by synoptic and satellite
observations and model results• Conclusions

Introduction: Dust cycle (Shao, 2008)
Radiationreflection,absorption
Cloudcondensation nuclei

Transport

Drydeposition

Wetdeposition
Dustemission• Dust emission is a key
component of the global
mineral-dust cycle.
• Dust cycle includes emission,transport and deposition of dust,
and the atmospheric processes
such as condensation nuclei forcloud formation and radiationreflection and absorption.
• The estimated global dust
emission is 2000 Mt yr−1.
• Aerosols have a net effect ofglobal cooling.

Introduction of dust storms in Mongolia• Natural zones• 34.6% of territory is thedry land areas, of which
28.4% -Desert steppe(Gobi) & 6.2% -theDesert.

DSSs frequently occur in the Gobi
Desert in spring due to strong winds,
scarce vegetation, and dry soil
conditions.
DSSs are natural disaster phenomenathat can have negative and directconsequences, including loss of life,
delays to aviation, interruptions to railand vehicular transport, and reductions
in pasture for livestock. DSSs havelong-term effects regarding soil erosion,
sand movement, and desertification
processes (Natsagdorj et al., 2003).
The dust source area of Northeast
Asia (target area: 35–45°N, 100–115°E)
has significant influence on the level of
Asian dust in Japan (Kimura, 2012a,2012b; Kimura and Moriyama, 2014).

Distributions and trend of dust storms inMongolia
Number of dusty days /32 stations, 1960-2015/.

• Distributions of dust storms using number of dusty days
(1960 -1999).
• Dust events have increased in the arid and semi-arid
regions of Mongolia and China during last decade(Shinoda et al, 2011)

Expected Warning criteria for wind & dust event• Warning criteria for wind & dust/sandstorm events(The Mongolian Government’s 286th Resolution, 2015, Annex 5.2: A list of
meteorological hazardous phenomena)

Phenomenon

Intensity for weather
warning

Strong wind Wind speed ≥ 18 m s-1(Gale ≥ 24 m s-1 )Dust storm

Intensity for severe weather warning

Very strong wind ≥ 24 m/s in thesteppe, ≥28 m/s in the Gobi withgale 34 m/s

Visibility ≤ 1000 m
Duration ≥ 3 h• Intensity
Type of dust/sand storm
classifications ofdust and sandstorm Severe dust storm
events using
Regular dust storm
visibility criterion
Slight dust storm(Manual, 2014, Volume14, Part 212, p.93-94).

Visibility, m≤ 50

51-1000> 1000Characteristics of the severe dust
event over the Mongolian Gobi
in 3-5 March, 2016

Severe dust storms• Severe dust storms refers to one of thedangerous meteorological phenomena with thepotential to cause damage, serious social
disruption, or loss of human life.
• The NAMEM observing and forecast system
helps reduce disaster risks by providing
information for early warnings.
• Alerts & Warnings for severe weatherdelivered by Radio, TVs, real-time web
displays, hand-phones etc.

Land surface condition: vegetation & snow
• Summer drought in theend of Aug.2015• Red/yellow colors showdrought.
• Vegetation was less.

• Winter snow in the end ofFeb.2016• There is no snow cover overthe Gobi Desert area
• Soil moisture was less.

Land surface condition:
Soil moisture at 2 sites in the Gobi Deserts• SM at 5 cm depth was 6.0% and 6.6% at Erdene
and Tsogt-Ovoo sites, respectively, during thedust event.
• SM less than 6.0-6.6 are critical values of soilmoisture for dust emission (Nickling, 1978, Kimura et at al.,2009, Abulaiti and Kimura, 2011, Jugder, 2015)

Weather condition at the surface
ECMWF model results, surface pressure at initial time (+00h)

12 UTC, 03 Mar.2016

00 UTC, 04 Mar.2016• A cyclone formed overthe lee side of theKhangai and Khuvusgul
Mountains and generated
the strong dust event.
12 UTC, 04 Mar.2016

Weather condition: 500hPa &700 hPa
ECMWF model results, 500hPa at initial time (+00h)

LL

12 UTC, 03 Mar.2016

L00 UTC, 04 Mar.2016

12 UTC, 04 Mar.2016

LObservations of 700 hPa, 00UTC and 12 UTC, 03 Mar.2016, 00UTC, 04 Mar. 2016

Max. wind speeds and dust storms and over Mongolia
in 3-5 March 2016

Warning level:
Strong wind ≥18 m/s with gale
24 m/sVery strong wind ≥ 24 m/s in thesteppe, ≥28 m/s in the Gobi withgale 34 m/s• Slight and moderate DSS• Severe dust storms

Number of stations, at which wind speeds≥16m/s and visibilities ≤ 2 km.

• Max. wind speed was more than 28 m/s at 6 stations, 21-28m/s at 38 stations & 16-20 m/s at 66 stations on 4 March.
• Visibility was less than 50 m at 7-12 stations, 200-500 m at
10 stations on 4 March due to dust storms and snowstorms.

Number of stations observed severe dust storms• According to the Manual on Codes, WMO No. 306(1995), code figures 30–35 shall be used only when
dust or sandstorms occur at the time of observation at
fixed surface stations:•
30 to 32 — Slight or moderate DSS.
•
33 to 35 — Severe DSS (WMO No. 306, Code Table 4677).
Number of stations withdust storms coded by 33-35
was 15-25 from 20:00
o’clock 3 Mar. to 20:00
o’clock 4 Mar.

Observed wind speed, PM10 and Visibility
Site nameMaximum windspeed averagedby 10 min, m/s

PM10, µg/m3

Measured minimum
visibility, kmDalanzadgad

20.4

1682

Ins.failure

Tsogt-Ovoo

20.8

1268

Ins.failure

Sainshand

20.6

350

0.6
(< 1 km during 3 hours)

Zamyn-Uud

23.3

1789

0.3
(< 1 km during 8 hours)

Erdene24.5-------

Measured Max. wind at Dalanzadgad, Sainshand,
ZamynUud and Erdene sites

Measured dust concentration and visibility

Visibility coded by 90-98 over Mongolia in 3-5 Mar.

• Visibility dropped to less than 50 m.

Mie-Lidar extinction coefficient
Dust height
1.5 kmDust height
1.25 kmPM10 by the MGL-ADAM model at initial times

00UTC 03 Mar.(+00h)

12UTC 03 Mar.(+00h)

00UTC 04 Mar.(+00h)

12UTC 04 Mar.(+00h)

MGL-ADAM model result:valid at
14 LST, 04 Mar. 2016(+06h)
AOD

PM10

Satellite image by MODIS,Aqua/Terraat 14:08 LST, 04 Mar. 2016

Warning forecast validation• Alerts & Warnings: Custom alerts for severe weather delivered by wayof email, real-time web displays or other electronic means.
• Verification for weather warning was 90-96%, but 57% in 4 March(overestimated spatial distribution).
• Verification for severe weather warning 87-92%.
• POD were 82-100% for both WW and SWW.

Daily forecast validation (by 28 stations)• Wind forecast verification was 79-86% in thestarting day of the dust event and 91.0-96.4%
during dust storm days.
• Forecast verification of the dust storm and snow
storm was lower in 3 March as 78.6% and 66.1%.

The severe storm impacts
Consequences
Missing herders
Weather-boundautomobiles / people
Motorbikes

Number44
17 / 883• Severe dust storm and snowstorm caused serious
social trouble, fortunately there was no loss of humanlife.

Conclusions• The dust event observed in 3-4 March was thestrongest storm in Mongolia in spring of 2016.
• The lee cyclone formed on the leeward(downwind) side of the Khangai, Khuvusgul
mountain barriers and developed as upper-level
cyclone.
• This lee cyclone produced major windstorms anddust storms downstream of the mountain barrier.
• The dust storm covers the Gobi Desert areas in
the southern part of the country, while snowstorm
covers the northern part.

Conclusions• The dust event was specific because it was thestrongest dust storm in this year of 2016.
• Measured max. wind was 32 m/s during thedust event. Lowest visibility was less than 50m.
• Temporal forecasts were good but spatial
forecasts had some mistakes.
• There was no loss of human life.

Thank you for your attention