Sandstorm hits Beijing China

March 16th, 2021 |


Himawari-8 Dust RGB imagery, 0000 UTC 13 March 2021 through 2300 UTC 16 March 2021

 

 

 

The BBC reported that Beijing, the Capitol of China, was hit on 15 March by the worst sandstorm in a decade (link).  The linked-to article noted pollution levels 160 times the recommended limit! The dust and sand that overspread the city originated in Mongolia, and the dust RGB animation above (click here for an animated gif), shows dust appearing on 14 March and spreading rapidly southeast behind a propagating extratropical cyclone.  Multiple mid-layer clouds somewhat interfere with the dust/sand detection (bright red/magenta in the dust RGB shown), but the origins in Mongolia after 0600 UTC on 14 March, and the quick spread south by 1800 UTC on 15 March are apparent.

The toggle below compares Himawari-8 true-color imagery and the dust RGB at 0330 UTC on 15 March.  The dust/sand is apparent in the True Color imagery as well as in the RGB.

Himawari-8 True Color Imagery and Dust RGB, 0330 UTC on March 15 2021 (Click to enlarge)

Himawari-8 imagery is courtesy JMA.  Image processing used Geo2Grid software.  This animation of surface analyses from 13-16 March 2021 (courtesy KMA) was created by Scott Bachmeier.

Smog and poor air quality in Beijing, China

November 30th, 2015 |

Suomi NPP VIIRS true-color images [click to play animation]

Suomi NPP VIIRS true-color images [click to play animation]

The sequence of 5 daily Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images shown above are centered on Beijing in northeastern China — these images (viewed using RealEarth) showed the transition from the Beijing area being sunny and snow-covered on 26 November to enshrouded in dense smog on 30 November 2015. The smog exhibited a distinct gray-colored appearance, in contrast to the brighter white clouds and snow cover. Much of this smog was driven by the burning of coal, both on a local level and by regional power plants (as discussed in this Capital Weather Gang blog post).

The corresponding daily time series plots of surface weather data at Beijing Capital International Airport (below) revealed that the surface visibility remained below 1.0 statute miles for extended periods. Although not indicated on the 26 November plot, the surface visibility began at 19 statute miles on that day, before the wind speeds became 4 knots or less beginning at 10 UTC and the visibility eventually began to decrease.

Daily time series plots of Beijing surface data [click to play animation]

Daily time series plots of Beijing surface data [click to play animation]

Major flooding event in Beijing, China

July 21st, 2012 |
FY-2E 0.73 µm visible channel images (click image to play HD animation)

FY-2E 0.73 µm visible channel images (click image to play HD animation)

A major flooding event occurred in the Beijing, China area on 21 July 2012, as the heaviest rainfall in over 60 years caused at least 77 fatalaties, cancelled over 500 airport flights, and forced more than 65,000 people to be evacuated. Much of the city averaged around 7-9 inches of rainfall within a 10-hour period, with the heaviest total rainfall accumulation being 18.1 inches (460 mm) in the Fangshan District of Beijing. McIDAS images of 1.25 km resolution 0.73 µm visible channel data from the Chinese FY-2E satellite (above; click image to play HD animation) showed an elongated band of clouds with embedded thunderstorms oriented from southwest to northeast across much of northeastern China. The small green box denotes the location of Beijing International Airport.

While there are some navigation issues associated with the FY-2E satellite (as noted by the amount of image drift during the animations), the position of the satellite at 105º E longitude offered a good viewing angle for this particular event. For a more detail meteorological analysis, see “Beijing flood of 21 July 2012” by Richard Grumm, NWS State College PA.

5-km resolution FY-2E 10.8 µm IR channel images (below; click image to play HD animation; also available as a QuickTime movie) revealed the development of very cold cloud top brightness temperatures (-60 to -75º C, red to black to white color enhancement) with some of these embedded thunderstorms, with evidence of a period of back-building of convection in the vicinity of Beijing after around 15 UTC.

FY-2E 10.8 µm IR channel images (click image to play HD animation)

FY-2E 10.8 µm IR channel images (click image to play HD animation)

5-km resolution FY-2E 6.8 µm “water vapor channel” images (below; click image to play HD animation) indicated a pronounced warming/drying signature (yellow colors) associated with a deepening shortwave trough that was approaching from the northwest. This approaching trough may have played a role in helping to enhance synoptic-scale upward vertical motion across the Beijing region, creating a more favorable enviroment supporting the formation and maintenance of strong convection.

FY-2E 6.8 µm water vapor channel images (click image to play HD animation)

FY-2E 6.8 µm water vapor channel images (click image to play HD animation)

A comparison of 375-meter resolution Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel imagery at 05:16 UTC (below) showed the development of some of the initial areas of embedded deep convective elements just to the southwest (upstream) of Beijing (station identifier ZBAA).

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

A time series of Beijing rawinsonde data Skew-T plots (below) showed the moistening of the atmosphere on 21 July, with the total precipitable water peaking at 50.4 mm (1.98 inches) at 12 UTC. The subsequent arrivial of dry middle-tropospheric air associated with the approaching shortwave trough can be seen after 00 UTC on 22 July, as Precipitable Water (PW) values dropped to 26.4 mm or 1.04 inch by 12 UTC.

Beijing, China rawinsonde data plots

Beijing, China rawinsonde data plots

Explosion in Tianjin, China

August 12th, 2015 |

Himawari-8 (3.9 µm, top), MTSAT-2 (3.75 µm, middle) and COMS-1 (3.75 µm, bottom) shortwave infrared imagery, times as indicated [click to animate]

Himawari-8 (3.9 µm, top), MTSAT-2 (3.75 µm, middle) and COMS-1 (3.75 µm, bottom) shortwave infrared imagery, times as indicated [click to animate]

A storage facility in Tianjin, China exploded shortly after 1500 UTC on 12 August 2015 (media story). Himawari-8, MTSAT-2 and COMS-1 all viewed the explosion that generated a strong thermal signature in the shortwave infrared band (3.75 µm – 3.9 µm). The animation above shows the benefit of Himawari-8’s speedier scanning mode: the smoke clouds that emanate from the explosion are easily traced, and data gaps when Full Disk images are being scanned (around 1800 UTC) are not present. Superior spatial resolution of Himawari-8 infrared channels (2-km, compared to 4-km for COMS-1 and MTSAT-2) means hotter brightness temperatures are sensed as well. The fact that smoke resulting from the explosion was seen spreading northeastward, southeastward, and southwestward was due to a marked shift in wind direction with height, as seen in the nearby Beijing rawinsonde report.

The explosion exhibted a signal in other Himawari-8 AHI bands as well. Band 5, at 1.6 µm and Band 6, at 2.3 µm are shown below (animations courtesy of William Straka, CIMSS); Similar animations are available for 3.9 µm, 6.2 µm (very faintly visible in this upper tropospheric water vapor channel), 7.0 µm, 7.3 µm and 8.6 µm and 10.35 µm.

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to enlarge]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

A view of Himawari-8 shortwave IR imagery using the SSEC RealEarth web map server is shown below. In addition, an animation of Himawari-8 true-color images showing the dark smoke plume can be seen here.

Himawari-8 shortwave IR (3.9 um) images, displayed using RealEarth [click to enlarge]

Himawari-8 shortwave IR (3.9 um) images, displayed using RealEarth [click to enlarge]


========================== Added 14 August 2015 ===================

Suomi NPP VIIRS Day/Night Band (0.70 um) visible images on 9 August (before explosion) and 13 August (after explosion) [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.70 um) visible images on 9 August (before explosion) and 13 August (after explosion) [click to enlarge]

The Suomi NPP satellite overflew Tianjin before and after the explosion; VIIRS Day/Night Band images afford views that suggest power outages around the explosion site.