Introducing "Dzuds" An Example Of How Climate Change Can Make Things Colder, More Disastrous

Climate change is a likely cause of some severe,
dangerous and tragic weather in Mongolia. 

 I'm reluctant to blame every single weather event on climate change.

After all, we've always had extremes of heat, cold, rain, snow and other weather calamities. 

It's just that climate change has made most if not all of these events more likely. And sometimes more extreme than before. 

Severe cold and snow are - as you'd expect - are particularly tricky to blame on climate change. If the world is warming, why are you blaming that cold snap, that blizzard on humans belching greenhouse gases into the atmosphere?

However, scientists know that occasionally, climate change can make the jet stream do strange, loopy things, like sending a batch of super chilled Arctic air down into the mid-latitudes. Storms tend to produce heavier precipitation under a climate change regime. It can still be cold enough to snow, so every once in awhile an ultra wet storm can literally snow a region under.

This can happen anywhere, really.  Sooner or later, somebody gets ridiculously hot, ridiculously cold, or snowy or blizzardy or just plain weird. You can find case studies in a lot of places, at least in recent years. 

Which is why I'm bringing up Mongolia. And Dzuds. 

A dzud is a period of extreme cold, heavy snow and powerful winds in Mongolia.  As you'd expect, these things are dangerous 

Yale Environment 360 explains:

"Cold winters are typical in Mongolia. Livestock survive by moving, growing thick coats of fur and pawing through snow and ice to grasses. But this winter, herds are struggling through both a 'white' dzud, in which very deep snow hinders their access to grass, and an 'iron dzud, in which a brief thaw is followed by a rapid, hard freeze, locking pastures in ice."

In the past, a dzud would hit Mongolia about once a decade. But in the past decade, six of 10 years have had them. This is the second year in a row with a severe dzud. 

Yale Environment 360 again:

"As of the last week of February, the number of dead animals reached more than 2.1 million, rising from 600,000 two weeks earlier. Snowstorms have killed at least one people, including one child."

The deceased animals are a matter of life and death for Mongolians. The 65 million or so domesticated animals provide meat, milk and sources of fuel.  Herders sell animal hides, wool and cashmere4 to buy food and pay for their childrens' education. 

This winter's weather has plunged thousands of Mongolians into poverty. 

The reason we're talking about distant Mongolia is to illustrate the point that climate change isn't just about record breaking warmth and huge rainstorms.  The warming atmosphere can really screw up things in surprising, difficult ways, and can affect the population of a whole nation. Or nations.  

Here's how climate change is thought to be contributing to this mess:

The amount of yearly precipitation in Mongolia is about the same as it's always been, but its seasonal distribution has changed.  Summer droughts have become more likely, and those summers have become hotter. All this weakens livestock ahead of winter because they don't eat enough to store reserves for the harsh winters.

Wintertime snowfall has increased. As we mentioned, that makes it harder for animals to graze. The deeper, more persistent snow cover also refrigerates the air, making Mongolia's Arctic winters even more frigid.

Deep snow can make a routine Arctic outbreak anything but routine. For examples, check back here in Vermont. Almost all of our most intense historic winter cold snaps occurred with deep, fresh snow on the ground. 

Nobody knows for sure if this era of frequent dzuds in Mongolia will fade, or worsen.  As always, though, climate change brings added uncertainty to the table. 

 In Mongolia, that fact just brought some tragic results.  

Weird Geeky Weather: Record High Pressure And A Weird Subtropical Storm

World record setting high barometric pressures is
occurring in Mongolia. Above is a winter scene from that
nation's capital, Ulaanbaatar. 

 Weather geeks are geeking out over a possible world weather being set in Mongolia of all places.  

There, it appears the strongest high pressure system on record is freezing the region out. 

Reports are coming in of barometric pressure of 1093.5 mb or 32.29 inches, according to aviation meteorologist Michael Adcock

For comparison, on average, the barometric pressure is around 29.92  inches. Readings of 31 inches are extreme and quite rare. 

The extreme barometric readings in Mongolia will have to be verified by the World Meteorological Organization to become official. 

Strong high pressure systems are most likely in the northern hemisphere during the winter as cold, dense air builds up in Arctic regions.  Sometimes, these particularly cold systems head south, bringing frigid air to the mid-latitudes. This is when you're most likely to break high pressure records. 

For instance, some of the highest barometric readings here  in Vermont - a little over 31.10 inches  -occurred with an Arctic high pressure system in 1920 that brought temperatures in the region to the minus 20s and 30s. 

True to form, it's frigid in Mongolia.  This nation is normally bitterly cold in the winter anyway.  Normal low temperatures this time of year in the capital Ulaanbaatar are around -10.  Low temperatures in this likely record strongest high pressure there are in the minus 30s. 

By the way, in and of itself very high or very low barometric pressure is not dangerous to humans. Only the weather associated with these phenomenon.  Obviously the frigid weather in these Arctic high pressure systems is dangerous.

Very low pressure is associated with intense storms, which of course tend to be risky. 

RARE SUBTROPICAL STORM

A subtropical storm named Oquira has formed in the Atlantic Ocean off the coast of Uruguay, South America. This area doesn't usually have much in the way of tropical storms. 

Tropical and subtropical storms depend on warm ocean water to develop. The South Atlantic between South America and Africa tends to be relatively chilly due to ocean currents, so this type of storm is rare off the coast of South America.   

It doesn't look like much but this is a satellite view of
Subtropical Storm Oquira off the coast of 
Uraguay, South America.  Subtropical storms
are rare in this region. 

Also, there tends to be strong upper level winds in the area off of South America, which discourages tropical storms from forming. 

This is the third subtropical storm to form in the Atlantic off of South America this year, which set the record for the most such storms in the region in a single year. 

This of course, is in the same year in which a record was set for the most tropical storms in the Atlantic north of the equator.  (As we know, tropical storms and hurricanes are much more common in the Atlantic between North America and Africa).

Subtropical storms are hybrids between regular old storms which have colder cores relative to the atmosphere around them, and tropical storms, which have warm cores. 

This storm - Oquira- has no chance of developing into a hurricane.  Only one storm in the South Atlantic has been known to become a full-fledged hurricane. That was Hurricane Catarina in 2004, which caused a lot of damage in southern Brazil.