MTSAT-2 6.75 µm water vapor channel images (click image to play animation)

A large area of low pressure over the Southern Ocean between Australia and Antarctica on 07 January – 08 January 2012 (surface analyses) exhibited a beautiful signature of an occluding cyclone on 5-km ressolution MTSAT-2 6.75 µm water vapor channel imagery (above; click image to play animation). This storm prompted the issuance of Gale Warnings for widespread areas of winds of 30-45 knots producing high seas.

A closer view of the MTSAT-2 water vapor imagery (below) revealed very intricate detail to the plume of dry air wrapping into the ceter of the storm, along with several small vortices of dry air that became cut off and isolated along the periphery of the system as it began to decay just southwest of the island of Tasmania.

MTSAT-2 6.75 µm water vapor channel images

MTSAT-1R 10.8 µm IR channel images

MTSAT-1R 10.8 µm IR channel images from the CIMSS Tropical Cyclones site (above) showed Category 1 Tropical Storm Thane (06B) in the Bay of Bengal, moving toward the east coast of India on 28 December 2011.

Contours of 850-200 hPa satellite-derived deep layer wind shear overlaid on MTSAT-1R 6.75 µm water vapor channel images (below) indicated that Thane was in an environment of low wind shear, which favored some intensification prior to making landfall.

MTSAT-1R 6.75 µm water vapor channel images + Deep layer wind shear

It is interesting to note that the MIMIC Total Precipitable Water product (below) showed the northern counterclockwise circulation of Tropical Storm Thane and the southern clockwise circulation of Tropical Storm Four (04S) — each drawing moisture from the Inter-Tropical Convergence Zone (ITCZ).

MIMIC Total Precipitable Water product

===== 30 December Update =====

Tropical Storm 04 S intensified in a similar low wind shear environment, becoming Tropical Cyclone Benilde in the South Indian Ocean. Benilde was forecast to intensify, with wind gusts up to 140 knots. Meteosat-7 visible/shortwave IR images with an overlay of ASCAT scatterometer surface winds (below) showed the structure of Benilde.

Meteosat-7 visble/shortwave IR imagery + ASCAT surface winds

MTSAT-1R 10.8 µm IR images (click image to play animation)

MTSAT-1R 10.8 µm IR images from the CIMSS Tropical Cyclones site (above; click image to play animation) showed a fairly compact cluster of cold convective cloud tops associated with Tropical Storm Washi as it moved westward toward the Philippines during the 15-16 December 2011 period.

A closer view using MIMIC microwave imagery (below) also showed a relatively small area of enhanced brightness temperatures (representing heavy precipitation) crossing Mindanao Island in the southern Philippines on 16 December.

MIMIC microwave imagery

However, AWIPS images of the MIMIC Total Precipitable Water (TPW) product (below; click image to play animation) revealed that Tropical Storm Washi was embedded within a long fetch of very rich tropical moisture, with TPW values in excess of 60 mm or 2.4 inches (darker red color enhancement). This abundance of moisture helped to fuel over 10 hours of heavy rainfall, which resulted in widespread flash flooding and reports of over 900 deaths in the Philippines.

MIMIC Total Precipitable Water product (click image to play animation)

MTSAT-1R 6.7 µm water vapor channel images

McIDAS images of MTSAT-1R 6.7 µm water vapor channel data (above) showed an intense extratropical cyclone that was moving toward the Bering Sea region during the 07 November – 08 November 2011 time frame. Of particular interest was the presence of a very warm/dry (dark black) circular region within the dry slot sector of the developing cyclone, which could have been associated with a strong potential vorticity anomaly.

A color-enhanced comparison of MTSAT-1R and GOES-11 6.7 µm water vapor channel data (below; click image to play animation) demonstrated the difference that satellite viewing angle (MTSAT looking from the west; GOES-11 looking from the east) and satellite sensor spatial resolution (the MTSAT-1R water vapor channel is “4 km” at nadir, while the GOES-11 water vapor channel is “8 km” at nadir) play in the ability to resolve such potentially important dynamical features. The core of the aforementioned MTSAT-1R dry feature moved directly over Shemya Island around 12:00 UTC on 08 November (MODIS IR image with surface analysis), where a surface wind gust of 83 mph was recorded at Shemya Air Force Base. Then, once the storm began to move northward over the Bering Sea, a more “curved banding” structure was seen on water vapor imagery as the cyclone began to wrap filaments of dry air around the deepening storm center. Although the sun angle was low, some of the “banding structure” could be seen in GOES-11 0.65 µm visible channel images.

MTSAT-1R (left) and GOES-11 (right) 6.7 µm water vapor channel images (click image to play animation)

While the dry slot features began to lose their definition in the geostationary MTSAT-1R and GOES-11 water vapor images (in part due to the upward shift in the peak of the water vapor channel weighting function with increasing satellite viewing angle), a direct overpass of the Aqua satellite around 23:45 UTC on 08 November provided a nice view using the 6.7 µm water vapor channel on the MODIS instrument (below). Using the MODIS imagery, good dry slot structure could be seen, even after the storm had moved northward over the Bering Sea.

Aqua MODIS 6.7 µm water vapor channel image

A sequence of AWIPS images of 1-km resolution MODIS 11.0 µm and POES AVHRR 12.0 µm InfraRed data (below; click image to play animation) showed the storm at various phases as it was rapidly deeping during its northward trek over the Bering Sea.

MODIS 11.0 µm and POES AVHRR 12.0 µm InfraRed images (click image to play animation)

This ended up being one of the strongest Bering Sea storms on record — the winds exceeded hurricane force across a very expansive area, producing high seas and major coastal flooding and beach erosion along parts of western Alaska. At the Tin City Airways Facility Sector (located near the western tip of the Seward Peninsula), they reported sustained winds of 72 mph with gusts to 85 mph — and the minimum altimeter air pressure was 28.46 inches. A peak gust of 89 mph was reported nearby at Wales. As the storm moved over St, Lawrence Island, minimum altimeter air pressure readings were 28.21 inches and 28.28 inches at Gambell and Savoonga, respectively.

The entire evolution of the storm during the 08-09 November time period can be seen on an animation of 15-minute interval GOES-11 10.7 µm IR images (below; click image to play animation).

15-minute interval GOES-11 10.7 µm IR images (click image to play animation)

MTSAT-2 10.8 µm IR channel images (click image to play animation)

MTSAT-2 10.8 µm IR channel images (above; click image to play animation) showed Category 4 Typhoon Roke as it approached Japan during the 19 September – 20 September 2011 period. Roke exhibited a well-defined eye during this time. Massive evacuations were urged by the Japanese government as this strong tropical cyclone approached major population centers in southern Japan.

On an MTSAT-2 IR image with surface and ship reports plotted from the CIMSS Tropical Cyclones site (below), the large radius of strong winds could be seen from the ship report of 50 knots a fair distance east of the storm center.

MTSAT-2 IR image + surface and ship reports

MTSAT-2 0.72 µm visible channel images (below; click image to play animation) showed the eye on 20 September — and there was a hint of meso-vortices within the eye of Roke on the 05:01 UTC visible image.

MTSAT-2 0.72 µm visible channel images (click image to play animation)

Global montage of geostationary satellite images (click to play animation)

The “spinning globe” satellite image montage (above; click image to play animation) showed the cloud formations around the planet on Earth Day (22 April 2011). This product is created by combining data from 5 of the currently operational geostationary orbiting meteorological satellites (GOES-East at 75º West longitude, GOES-West at 135º West longitude, Meteosat at 0º longitude, Meteosat at 63º East longitude, and MTSAT at 145º East longitude), polar orbiting satellites, and a topographic background map of the Earth. The spinning globe product is created every 3 hours, and is available for either the latest time period or an animation covering the last 3 weeks.

MODIS IR image atmospheric motion vectors over the Arctic region

Polar-orbiting satellites such as the NASA Terra and Aqua platforms also provide us with valuable information over the polar regions of the Earth (which are not sampled well by geostationary satellites, due to the very large viewing angles). Cloud-tracked winds (or “atmospheric motion vectors”) can be calculated by comparing the location of features on successive images — examples of Terra and Aqua MODIS winds from 22 April 2011 over the Arctic region (above) and the Antarctic region (below) provide valuable input into numerical weather prediction models.

MODIS IR image atmospheric motion vectors over the Antarctic region

These are just a few examples of the diverse array of real-time satellite data and products that are available from the Space Science and Engineering Center at the University of Wisconsin – Madison every day.

GOES-11 0.65 µm visible channel images (click image to play animation)

McIDAS images of GOES-11 0.65 µm visible channel data (above; click image to play animation) showed an interesting “dark plume” feature that was moving in an arc from far northeastern Russia, across the East Siberian Sea and Chukchi Sea, and finally over far northwestern Alaska on 16 March – 17 March 2011.

When viewed from a more western angle using MTSAT-2 0.73 µm visible channel images (below; click image to play animation), the plume feature (which can be seen moving over far northwestern Alaska in the upper right portion of the images) also exhibited a darker appearance, similar to that seen on the GOES-11 visible imagery. This darker appearance was due to backward scattering of light from the particles within the plume.

MTSAT-2 0.73 µm visible channel images (click image to play animation)

AWIPS images of POES AVHRR 0.86 µm visible channel data (below) provided more of a “direct view from above”,  and revealed that the main body of the plume was basically transparent (allowing details of the sea ice to be seen through the plume).  However, the plume edges appeared to have some vertical structure, being thick enough to cast shadows onto the sea ice below.

POES AVHRR 0.86 µm visible channel images

It is interesting to note that this plume feature did not exhibit any notable signature on POES AVHRR 12.0 µm IR images (below).

POES AVHRR 12.0 µm IR images

A series of MODIS true color Red/Green/Blue (RGB) images (below; courtesy of the GINA, University of Alaska) again showed the transparent nature of the main body of the plume feature, except for the thicker edges which  were casting shadows.

MODIS true color Red/Green/Blue (RGB) images (courtesy of University of Alaska, GINA)

Could this feature have been an aged volcanic plume that was being transported aloft over the Arctic? AWIPS images of the MODIS Volcanic Ash Mass Loading product (below) did display a few isolated very small patches exhibiting 1-10 tons per square kilometer of loading at 04:44 UTC on 17 March, but there was no temporal continuity when examining the Ash Mass Loading product before or after this particular time.

MODIS Volcanic Ash Mass Loading product

Volcanic Ash Height product

The corresponding MODIS Volcanic Ash Height product (above) indicated that these features were located at an altitude of 3-4 km, while the MODIS Ash Mass Effective Particle Radius product (below) showed values in the 3-5 µm range.

Volcanic Ash Particle Effective Radius product

However, rather than an aged volcanic ash plume, a more plausible explanation of the feature seen on satellite imagery is the long-range transport of smoke and pollution from industrial sources in northeastern China. A calculation of 96-hour backward trajectories using the NOAA ARL HYSPLIT model (below) indicated that air parcels arriving at 3 points along the plume at an altitude of 6-km had originated within the boundary layer over northeastern China on 13 March. MODIS images showing the thick haze over that region can be found on the US Air Quality “Smog Blog”.

NOAA ARL HYSPLIT back trajectories arriving at the 4km, 6km, and 8km altitudes

MTSAT-1R 0.68 µm visible channel images

MTSAT-1R 0.68 µm visible channel images (above) tracked the eye of Super Typhoon Megi making landfall across the northern portion of the island of Luzon in the Philippines on 17-18 October 2010.

The Morphed Integrated Microwave Imagery at CIMSS (MIMIC) product (below) showed the well-defined eye of Megi prior to making landfall, along with the effect that the rugged terrain of Luzon had on the typhoon before it later emerged into the South China Sea.

Morphed Integrated Microwave Imagery at CIMSS (MIMIC)

A Terra MODIS 11.0 µm IR image (below; zoomed-in version) revealed the eye and surrounding concentric eyewall structure of Megi at 02:30 UTC on 19 October — the coldest IR brightness temperature seen at that time was -82º C (purple color enhancement) to the south of the eye.

Terra MODIS 11.0 µm IR image

MTSAT-2 IR images

MTSAT-2 IR images from the CIMSS Tropical Cyclones site (above) revealed a well-defined eye associated with Super Typhoon Nida on 25 November 2009. Typhoon Nida underwent a period of very rapid intensification — increasing by 50 knots of speed in 12 hours — as seen on the CIMSS Automated Dvorak Technique plot (below). Low values of deep layer wind shear and warm sea surface temperatures were favorable factors aiding further intensification.

CIMSS Automated Dvorak Technique (ADT) intensity estimate plot

An AWIPS image of the MTSAT-2 IR channel with an overlay of ASCAT scatterometer winds (below) showed a core of strong winds (greater than 48 knots, red wind vectors) surrounding the eye of Nida; the maximum ASCAT wind speed at that time was only 62 knots in the northern quadrant (but ASCAT wind speeds in excess of 34 knots tend to be underestimated).

MTSAT-2 IR image + ASCAT scatterometer winds

A MODIS 11.0 µm IR image (below) depicted the very cold cloud tops within the eyewall region, with a minimum value of -87º C (black to gray color enhancement). However, there were some incredibly cold cloud tops of -97º C (violet color enhancement) in one of the outer bands in the northwest quadrant of Nida.

MODIS 11.0 µm IR image

An animation of the MIMIC morphed POES microwave images (below) showed a contracting eyewall as the typhoon was experiencing rapid intensification just southwest of the island of Guam.

MIMIC morphed microwave image animation

UPDATE: A microwave image from the DMSP SSM/IS instrument (below) revealed a concentric eyewall structure at 19:43 UTC. A couple of hours later, the 21:00 UTC advisory from the Joint Typhoon Warning Center listed the winds of Super Typhoon Nida at 160 knots with gusts to 195 knots!

DMSP SSM/IS microwave image

MTSAT-1R visible images

One of the worst dust storms in the past 70 years swept across a large part of eastern Australia on 22 September – 23 September 2009 (Daily Mail Online photos). A sequence of MTSAT-1R visible images (above) showed the progression of the large dust cloud as it moved eastward during the daylight hours. Note the appearance of “lee waves” along the top of the dust cloud, as the strong winds interacted with the high terrain of the Great Dividing Range. An undular bore could also be seen forming out ahead of the cold front, over the offshore waters of the South Pacific Ocean.

The surface meteorogram for Brisbane, Australia (station identifier YBBN) is shown below; note that the surface visibility dropped to 0.2 km (0.1 mile) as the cold front passed, and following the frontal passage the dew point dropped from +16º C (61º F) to -16º C (+3º F).

Brisbane, Australia surface meteorogram

A larger-scale view of the dust cloud feature could be seen using MODIS true color imagery from the NASA MODIS Rapid Response site (below, viewed using Google Maps). See also the NASA  MODIS Image of the Day.

MODIS true color image