According to the Nov. 30 online Argus North American Fertilizer Newsletter, heavy rain is expected in the South and Pacific Northwest, while warmer-than-normal temperatures are forecast for most of the U.S. for the first 10 days of December. At the same time, near normal temperatures are likely along the East Coast and Southeast U.S., according to the National Weather Service.
But NWS forecasts that colder than usual temperatures will be limited to Florida’s Atlantic coast and the Northeast U.S. Much of this erratic climate behavior can be blamed on a rather whimsical polar jet steam branch in the northern hemisphere.
What remains to be seen is whether that northern polar jet stream branch will jut way south in a fashion similar to what took place last Dec. 13. At dawn that day, our remote-sensing thermometer logged an 8.5º F reading for our part of downtown Hartwick. When the temperature drops this low (or actually just drops to or below 14º) sublimation takes place.
During sublimation, water in the form or ice or snow can evaporate at or below this temperature threshold without first having to go through the liquid phase. An accompanying benefit is that when air temperatures descend to this level, water vapor liberated from ice and snow rapidly forms low-hanging cloud cover. This helps seal in Earth’s warmth. Without this cloud shield, much of our planet’s geothermal heat would surge into the upper atmosphere due to radiational cooling.
Sublimation has some negative traits, however: bare soils, lacking cover crops, definitely freeze dry, meaning that the affected soils rapidly lose moisture. Also, dried soil particles – especially clays and silts loosened by freezing/thawing action – are vulnerable to wind and water erosion. The best way to dodge any threat to soil and moisture loss due to sublimation is to minimize the amount of time that soil lays bare and unprotected. The best way to harness the benefit of expanding ice – integral to freezing/thawing – is to determine the lime needs of the fields in question.
If your soil test results indicate the need for lime, the best time to apply it would be between when I write this column and when the next major snowfall arrives. The second-best time would be as soon after that snowfall that field conditions become passable.
In the coming weeks, there will be a lot of freezing/thawing, an occurrence which increases the effective neutralizing value of liming material. Most commercial lime suppliers stress that lime spreads easier with air temperatures over 20º. If we do get some of those “warm” spells in the weeks ahead, let’s take advantage of them by “sweetening” soils that need it.
Mentioning dust once more, particularly on bare corn stubble ground, should you see these minute soil particles blowing from bare ground – maybe as part of a dust devil – commit to planting winter forage immediately following 2024’s corn silage harvest.
Continuous freezing/thawing tends to create potholes in roads during winter in regions like ours. Because of its greater volume (thus lower density), ice floats. Thus, the visible part (the tip) of an iceberg is only about one-tenth of its mass. Once I accidentally conducted an experiment dealing with the freezing/expansion trait of seltzer in an unopened can. One frigid morning, I opened my truck’s door only to see crystalline ice formations on the inside of the vehicle’s windshield. The truck’s defroster made light work of the ice crystals. Had the liquid been sugar-laden soda instead of seltzer, cleaning the windshield would have been much more of a challenge.
Actually, the sugar in the soda might have depressed the freezing point to where the can might not have ruptured in the first place. To be sure, it is natural sugars in many living plant species with their own antifreeze properties that enable them to survive cold in many situations.
Attempting not to be beaten by late autumn and winter ice and snow, I keep plenty of salt handy just to chase away the ice that I can’t get with the snowblower, snow shovel or push broom. These tools move water, doing so through physical changes. But salt impacts water’s chemical characteristics. The most common salt is sodium chloride (NaCl) – kitchen table salt. Simply defined, a salt is the end product of an acid reacting chemically with a base. What actually happens is that NaCl couples with water molecules reacting with them chemically, yielding two liquids: dilute hydrochloric acid (HCl) in solution and dilute sodium hydroxide (NaOH) also in solution. These liquid compounds when dissolved take up less volume than the original ice and salt. The remaining ice crystals restructure with a cracking sound – again, a chemical change.
Even without the addition of salt, water does some pretty interesting things. We know that with most compounds, as the temperature of the liquid decreases, the density increases as the molecules become more densely packed. But this pattern does not hold true for ice being formed from liquid water; in fact, the opposite occurs. This is because in liquid water, each water molecule is hydrogen-bonded on average to 3.4 other water molecules in a very precise lattice-type structure very similar to jacks.
This means that 100 grams of water at 34º has a volume of 100 milliliters (ml). When that 100 grams of water becomes ice, it now occupies 110 ml of volume. With limited space, that is pretty serious crowding among the water molecules. This crowding results in enough force to break rigid containers including barn water lines, engine blocks and an unopened can of seltzer on the front seat of my truck.
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