Record Russian Rain Runoff Responsible for Rapid River Rise

Sorry, I couldn’t help myself with that title.  Last time we looked at flooding in Russia, it was in the western parts – generally near Moscow and primarily along the Oka River – and caused by rapid melting of record spring snowfall. This time, flooding is occurring in Russia’s Far East, primarily along the Amur River, caused by heavy rainfall related to monsoon wind patterns in the region – record levels of flooding not seen before in the 160 years Russians have settled in the area.

Unfortunately, this natural disaster is affecting more than just Russia. In China, many people are dead or missing as the result of flooding. (The figure of “hundreds dead or missing” includes flooding caused by typhoons Utor and Trami in southeastern China, flash flooding in western China, and the subject of today’s post: river flooding in northeastern China and far east Russia.) The Chinese provinces of Liaoning, Jilin and Heilongjiang have been hit particularly hard with persistent, heavy rains since late July, as have areas just across the border in Amur Oblast, Khabarovsk Krai and the Jewish Autonomous Oblast in Russia.

A few more facts: Heilongjiang is the Chinese name for the Amur River. It translates to English as “Black Dragon”. The Mongols called it Kharamuren (“Black Water”), which, I assume, the early Russian settlers shortened to Amur. It is the longest undammed river in the Eastern Hemisphere and the home to the endangered Amur leopard and Amur tiger. Since 1850, the Amur River has been the longest piece of the border between China and Russia. Now, in 2013, the Amur River has reached the highest levels ever recorded.

Backing up a bit, here’s what the area looked like according to “Natural Color” or “pseudo-true color” VIIRS imagery back in the middle of July:

VIIRS false-color RGB composite of channels I-01, I-02 and I-03, taken 03:27 UTC 14 July 2013

VIIRS false-color RGB composite of channels I-01, I-02 and I-03, taken 03:27 UTC 14 July 2013

As always, click on the image, then on the “2368×1536″ link below the banner to see the full resolution version. Here’s what the same area looked like about a month later:

VIIRS false color RGB composite of channels I-01, I-02 and I-03, taken 03:14 UTC 21 August 2013

VIIRS false color RGB composite of channels I-01, I-02 and I-03, taken 03:14 UTC 21 August 2013

Notice anything different? The Amur River has overflowed its floodplain and is over 10 km (6 miles) wide in some places. Just downriver (northeast) from Khabarovsk, the flooded area is up to 30 km (18 miles) wide!

Pay attention to Khabarovsk. Back in 1897, the Amur River crested there with a stage of 6.42 m (about 21 feet in American units), which was the previous high water mark. On 22 August 2013, the river stage reached 7.05 m (23 feet) and was expected to keep rising to 7.8 m (25.6 feet) by the end of August. The map below (in Russian) shows the local river levels on 22 August 2013. It came from this website.

Amur River levels at various locations in Khabarovsk Krai, Russia on 22 August 2013.

Amur River levels at various locations in Khabarovsk Krai, Russia on 22 August 2013.

Note that Khabarovsk in Cyrillic is Хабаровск (the black dot in the lower left), and Amur is Амур. The blue numbers represent the river stage in cm. Red numbers indicate the change in water level (in cm) over the last 24 hours. The colored dots indicate how high the river level is above flood stage according to the color scale (also in cm). The river at Khabarovsk is more than 4 meters (13 feet) above flood stage.

Not impressed by comparing a “before” and “after” image? Here’s an animation over that time period (14 July to 21 August 2013), with images from really cloudy days removed:

Animation of VIIRS false-color composites of channels I-01, I-02 and I-03

Animation of VIIRS false-color composites of channels I-01, I-02 and I-03. Click on the image, then on the "1184x768" link below the banner to view the animation.

You have to click through to the full resolution version before the loop will play. In order to not make the world’s largest animated GIF, the I-band images in the loop have been reduced in resolution by a factor of 2, making them the same resolution as if I had used M-5, M-7 and M-10 to make this “Natural Color” composite.

The Day/Night Band is not known for its ability to detect flooding at night, but it also saw how large the Amur River has become:

VIIRS Day/Night Band image, taken 17:27 UTC 20 August 2013

This image was taken on 20 August 2013, which just so happens to be the night of a full moon. The swollen rivers are clearly visible thanks to the moonlight (and general lack of clouds).

Khabarovsk is a city of over 500,000 people and would require a major evacuation effort if the river reached the expected 7.8 m level. Over 20,000 people have already been evacuated in Russia alone (and over a million people in China) according to this report. Oh, and at least two bears.

This heavy rain and flooding makes it all the more surprising that, a little further north and west in Russia, there have been numerous, massive wildfires. Check out this “True Color” image from VIIRS, taken on 16 August 2013:

VIIRS"True Color" composite of channels M-3, M-4 and M-5, taken 03:12 UTC 16 August 2013.

VIIRS"True Color" composite of channels M-3, M-4 and M-5, taken 03:12 UTC 16 August 2013.

See the supersized swirling Siberian smoke spreading… OK, I’ll quit with the alliteration. Here’s the smoke plume on the very next overpass (about 90 minutes later) seen on a larger scale:

VIIRS "True Color" composite of channels M-3, M-4 and M-5, taken 04:52 UTC 16 August 2013.

VIIRS "True Color" composite of channels M-3, M-4 and M-5, taken 04:52 UTC 16 August 2013.

A strong ridge of high pressure with its clockwise flow is trapping the smoke over the region. In this image you can see quite a few of the smoke sources where the fires are still actively burning. Look in the latitude/longitude box bounded by 98 °E to 105 °E and 59 °N to 61 °N. By the way, that’s Lake Baikal on the bottom of the image, just left of center.

A quick back-of-the-envelope calculation indicates that the area covered by smoke is roughly 500,000 km2. (Of course it is complicated by the fact that the smoke is mixing in with the clouds, so it is hard to define a true boundary for the smoke on the north and west sides.) That puts it in the size range of Turkmenistan, Spain and Thailand. If that’s not a good reference for you, how’s this? The smoke covers an area larger than California and smaller than Texas.

These fires have burned for more than a month. This article from NASA includes a MODIS image from 25 July 2013 containing massive smoke plumes and shows that areas of central Russia (particularly north of the Arctic Circle) have had a record heatwave this summer. And here are a few more images of the smoke from MODIS over the past few weeks.

Heatwaves and fires and floods? Russia is all over the map. Literally. I mean, look at a map of Asia – Russia is all over that place. It even spreads into Europe!

Abafado Bruma Seca

Hopefully, Google Translate didn’t steer me wrong on the meaning of “abafado”. “Bruma seca” is a term used by Portuguese and Spanish speakers that literally translates to “dry mist”. It is typically used to refer to thick haze or the brownish air caused by dust and, more specifically, to the Saharan Air Layer (scroll down a bit on this Weather Underground blog post for nice description of what that is).

We’re speaking Portuguese today because we are re-visiting Cape Verde, an island nation where people speak Portuguese. (Actually, many people speak a creole version called Kriolu kabuverdianu that has Western African elements added to the Portuguese.) Last time we visited Cape Verde, the islands were creating interesting waves and plumes in the atmosphere. This time, Cape Verde is buried under a plume – a plume of Saharan air that is so thick, you can barely see the islands:

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 15:07 UTC 30 July 2013

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 15:07 UTC 30 July 2013

I had to plot the map boundaries on the image just to see where the islands are. Otherwise, they would be lost in a sea of brown dust. Also, without the map, it’s difficult to find the shoreline of western Africa because the dust looks just like the Sahara Desert where it came from.

This image is (and the images to follow are) a “True Color” RGB composite. (As always, click on the picture, then on the “2442×1920″ link below the banner to see the full resolution image.) Unlike many previous true color images shown on this blog, these have been “Rayleigh corrected.” This means the impact of Rayleigh scattering by the molecules in the atmosphere has been removed. The reason for doing this is that it makes the surface easier to see and it better represents what people normally see when looking out of the window on an airplane. Dust particles, on the other hand, are Mie scatterers at visible wavelengths (refer back to that last link) so they still show up. In fact, this is one of the strengths of the True Color composite: it is quite sensitive to particulate matter in the atmosphere like smoke, smog, haze and dust.

The image above was taken on 30 July 2013, one day after the dust really started to be pushed off the African coast. It is not clear if the people of Cape Verde were forced indoors by this dust since I wasn’t able to find any news reports on it. The western edge of the dust plume (between 28° and 29° W longitude) almost looks like it is casting a shadow, which would indicate the dust is lofted pretty high in the troposphere in this image.

This dust plume pushed across the Atlantic Ocean over the following days. VIIRS passed over Cape Verde on 31 July 2013 (14:48 UTC) and captured this image:

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 14:48 UTC 31 July 2013

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 14:48 UTC 31 July 2013

Here, the dust plume extends from one side of the swath to the other – over 3000 km. On the very next orbit (16:29 UTC 31 July 2013), the plume can be seen on four consecutive data granules, extending almost to the middle of the swath. (The satellite covers a distance of over 2000 km over four granules.)

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 16:29 UTC 31 July 2013

VIIRS "True Color" RGB composite of channels M-03, M-04 and M-05, taken 16:29 UTC 31 July 2013

Hold on. What’s that strip of white-colored stuff extending north-northwest from 50° W longitude label? Some kind of white dust? That happens to be in a straight line? Nope. It’s what is called “sun glint” and it’s the same basic phenomenon as the glare you see looking out over a body of water without polarized sunglasses.  The dust is all the brown stuff on the right side of the image. That’s South America and the Lesser Antilles on the left side of the image.

If you click to the full resolution version of the image above, you may find that the image doesn’t seem very big considering it is made of four granules. (Its pixel size is 1600×1536. In contrast, the image above that is only two granules, yet is 3200×1536 in size.) That’s because I had to reduce the resolution of the data in order to plot it all without running out of memory on my computer. VIIRS has twice the resolution of what is shown in the latter image. (And this high resolution requires a lot of computing power to display!)

On 1 August 2013, the plume pushed even closer to the Lesser Antilles (although they are off the left side of this image).

VIIRS "True Color" composite of channels M-03, M-4 and M-05, taken 16:10 UTC 1 August 2013

VIIRS "True Color" composite of channels M-03, M-4 and M-05, taken 16:10 UTC 1 August 2013

Again, the resolution has been degraded by a factor of two. It is interesting to note that one granule covers an area of the Earth about 3040 x 570 km in size (1.7 million sq km, or 669,000 sq mi), so four granules is about 6.9 million km2. That’s 2.6 million square miles. In comparison, the size of the lower 48 states is about 3.1 million square miles (3.7 million square miles if you add on Alaska and Hawaii).  Now notice that the dust covers most of the last image. If you add on the area of the dust plume that stretches all the way back to Africa, you are talking about an area well over the size of the United States! By the time it arrives in the Caribbean, that dust better learn to speak Antillean Creole. It is a long way from Cape Verde.

So, what does all of this mean? It is often claimed that the presence of Saharan dust layers is bad for hurricane formation. Evidence for that claim is provided here and here. However, there are also scientists who refute that claim, which you can read about here. Scientists at the U.S. Geological Survey (USGS) have found that Saharan dust may be harmful to people and to coral reefs. According to this article in Nature, the dust is beneficial for the Amazon rainforest.

This event was also discussed on the Weather Channel. Compare his visible images to mine, which use only one color of the visible spectrum to my three color images. So, whether Saharan dust is good or bad, I think we can all agree that VIIRS is good!

UPDATE (5 August 2013): Remember the “split window difference”? It was mentioned the last time we visited Cape Verde. Here’s is a split window difference product produced at CIMSS that highlights the plume as it traveled across the Atlantic. This loop starts on 29 July and ends on 2 August 2013 and is made of data collected by the geostationary satellite MSG-3.

UPDATE (19 August 2013): Here’s another animation of the dust plume, made using observations from the Ozone Mapping and Profiler Suite (OMPS), one of the new instruments aboard Suomi NPP alongside VIIRS. (Actually, it’s on the opposite end of the satellite from VIIRS, so it’s not literally alongside VIIRS, but you get the idea.)