North Pole Weather 2/11/13

The sun will rise at 9:02 this morning, and set 8 hours 8 minutes later at 5:10 this evening. Sunset is now after 5; I’ll soon be able to attend afternoon lectures! It’s warmed up a little, but thankfully not so much that the roads were too slippery to attend the critique session yesterday afternoon.

We’ve had a little snow over the last week – enough that I’m thinking of getting the driveway plowed again. The all-wheel drive could handle keeping it rolled down if I were going in and out every day, but I’ve been making it out only about twice a week lately, and I’ve killed the engine backing out a time or two. The snow stake says the depth is approaching two feet, so at least we’ve about made up for the settling. I tried to crop the photo so the bottom of the photo is the base of the stake. I have not tried to walk out to the stake!

I got back the digitizations of the rest of the 35mm slides last week. Some I know I took are still missing; some I’d totally forgotten about were there. I took one group in 1978 when I visited a botanical garden in Wichita with my father and his second wife, 8 years after my mother died. I couldn’t remember the name of the place so I googled “public gardens Wichita” and finally found it: Bartlett Arboretum, in Belle Plaine, KS. Really a beautiful place, and we visited in tulip time. Now I need to get the 2 ¼ x 2 ¼ slides, the Super 8 movies and the videotapes done, but at least I have managed to look at the movies and see that some are worth saving.

North Pole Weather 9/24/12

The sun rose at 7:42 this morning and will set at 7:42 this evening, so will be above the horizon for a few seconds more than twelve hours. What, wasn’t the equinox several days ago? Yes, but as I said, the times of sunset and sunrise are determined by the top edge of the sun, adjusted for the refraction of the atmosphere. Here in Alaska the angle of sunrise and sunset is very shallow, which makes the day even longer relative to when the center of the sun is geometrically on the horizon.

Although it has been warm enough this past weekend, actually reaching 67°F Saturday, this is well above normal. It’s snowing in the northwest of the state, and it wouldn’t really surprise me to see a snow shower here, though I wouldn’t expect snow to stick yet. It won’t be long, though.

This colored-leaf variety isn’t even grown for its flowers.

I’ve taken in the plastic covers for the raised beds. I harvested the last of the beets, getting several over a pound, and the rest of the produce is pretty well dead. I might still be able to cut and freeze some rosemary sprigs from the beds closest to the house, since I didn’t get any rosemary potted up. I did get the potted mints and the geraniums in, though they still need pruning. The outdoor mints are still growing vigorously, as are the pansies, but most of the outdoor plants are through for the season. If I needed further proof that the lemon mint wasn’t quite a normal mint, its reaction to the frosts we’ve had should give it.

I’m not going to get everything done this fall, but I do need to get the hoses into the shed and some of the perennials cut back next week. I hope the snow holds off that long, and my cough gets better. The last day of the farmers’ market was yesterday, so I won’t be selling books there any more. I will, however, be editing—talked to my editor last week about doing the trilogy, and I’m working on the formatting and having a final read-through. So I’ll keep busy!

Jarn’s Journal Year 4 Day 64

Year 4 Day 64

I think last year the gather was longer than usual, because of Storm Cloud’s illness and possibly because of my presence. This year I can see more clearly why they have these meetings, and that not all the scattered bands come. Two are here for the first time in several years, one sent word they were not coming, and three simply did not show up.

Mostly, the business of the gather is arranging matings, formalizing them, and recognizing and welcoming children born since the last gather. Beyond that, it seems a time for meeting old friends, exchanging information, and just plain partying.

Did I mention that they have discovered that certain half-rotted fruits affect them rather strongly? They don’t seem to affect me, and I don’t even care for the taste. Some of the young men, in particular, can get downright wild and irresponsible when indulging. I was pleased to observe that Giraffe was not among them.

I am getting quite spoiled by the cooked food they bring me, and I am doing my best to make returns by presenting them with things they have difficulty in procuring for themselves. Salt and obsidian, I have found, are always welcome, as are foodstuffs from the jungle to the north. I have found a kind of tree in desert oases that produces a fruit even sweeter than figs, and these fruits, dried, last for months. The children love them. The men are adding water and trying to ferment them.

Songbird is quite definitely expecting. Strange — I almost feel like a grandfather-to-be. I hope the birth is not difficult for her, as some seem to be for these people. I suspect their heads have enlarged faster than their hips have broadened. The women of my people broaden far more in the hips when they are fertile, but only then. Songbird would have a hard time keeping up with her band if he hips had broadened enough to have a child easily.

This is part of the Journal of Jarn, a fictional human-like alien stranded in Africa 125,000 years ago, when the climate was much like today’s. As I complete each week’s episode, I add it to my author site. I apologize for the trimmed fronds on the date palm in the photograph. The ones Jarn found would obviously have been much shaggier, and the wild dates were probably smaller.

Radiation Frosts

It’s that time of year again. Time to get out the plastic and the floating row covers, and pack water-filled bottles among the rows of plants. It’ll be a while before the orange growers have to get out their smudge pots and fans, but here in Alaska the season for radiation frosts has started, and anyone with a growing garden is hoping for cloud cover at night.

Why?

Anything not at absolute zero (-460°F) radiates energy. The efficiency of this radiation varies, but most solids and liquids other than metal are very efficient. Most gasses are very inefficient, the so-called greenhouse gasses being exceptions. At the temperatures we live at, most of this radiated energy is in the thermal infrared.

The energy has to come from somewhere. Something like pavement may get its energy from deeper down, by conduction. Ever seen those warning signs that ice may form on bridges? That’s because a bridge doesn’t have as much thermal mass as a road on normal ground, so it can lose more energy and get colder at night.

Surfaces also gain energy from radiation. We’re all familiar with the sun’s radiant energy, or the energy of a fire, which we can feel on our faces. But building walls, for instance, also radiate in the infrared. If the radiating surface is about the same temperature as our skin, there is no net energy loss or gain, so we don’t feel the exchange as warm or cold.

Conduction from (or to) the air also has to be taken into account.

One final piece of the puzzle: surfaces radiate energy at a rate proportional to the fourth power of the absolute temperature and also proportional to the efficiency with which they radiate. In practice, energy radiated increases with temperature.

On a cloudy night, the clouds radiate to the ground at the temperature of the cloud base. Unless the cloud base is below freezing, this helps the temperature near the ground stay above freezing. But what if there are no clouds at night?

It depends on the temperature of the air aloft, and the amounts of carbon dioxide and water vapor in the air. The water and carbon dioxide radiate energy down to the ground, but not terribly efficiently. It the air is cold and dry, objects without much thermal mass, such as leaves, may radiate so much more energy than they receive that they cool below freezing even while the air temperature is above freezing. This is a radiation frost.

Of course the air is cooled by the cooling leaves and ground, so often the air temperature also goes below freezing. But the leaves freeze fist.

Why do plastic or row covers help? With a cover, the energy radiated comes from all of the air trapped below the cover, not just from the leaves. Cooling is slower. It can be made even slower by putting something with high thermal mass, like bottles of water, below the cover. Keeping the air mixed with fans also helps, because since the air is cooling from the bottom up, mixing warmer air down from aloft helps keep the plants warm.

I’m keeping an eye on the weather forecasts – especially clouds!

North Pole Weather 8/27/12

The sun rose this morning at 6:18 and will set this evening at 9:25 for 15 hours 7 minutes of daylight. Nautical twilight now starts before midnight, though astronomical twilight lasts all night—the sun never gets more than 18° below the horizon. And it’s not even getting to 35° above the horizon at noon.

The Dry Creek Fire, as visible about 5 miles from where I live.

Actually, astronomical night hasn’t meant much the last few days. August is finally acting like a Fairbanks August should. I really shouldn’t have been blogging about how dry it’s been—we were up to .53” rain for the month by Saturday night, and over half of that fell Friday and Saturday. Saturday was alternating sunshine and showers. Sunday was solid, steady rain, for a daily total of .82″, the most we’ve had in a single day for over two years. No flood worries; it was too dry to start with. The forecast for today is more of the same, but it’s still smoky, too.

Leaves are beginning to litter the lawn. I don’t need to worry about frost as long as it stays cloudy, but I’d better get the plastic out for the raised beds at the first sign the clouds will clear. We have cold air aloft, and while official low forecasts are still in the 40’s or possibly high 30’s, a radiation frost is certainly possible.

One branch on this tricolor geranium has reverted to normal zonal color, and needs to be pruned out. Otherwise, being more vigorous, it will take over.

The garden is still producing more zucchini than I can eat, though the beans have slowed down. Beets and chard are still producing, though beets will store. Looks like I’ll have quite a few to store this year.

I need to prune the potted plants (above) that I plan to bring indoors for the winter, and decide if I want to dig up one or two of the prettiest begonias. They will winter in the plant room, and even continue blooming for a while. I did cut out a branch of one of the colored-leaf geraniums that reverted to green—need to check the other two for reversions.

My blogging schedule will be a little erratic the next few weeks. I’ve joined GUTGAA (gearing up to get an agent) which will take some blog spots in September, and I’m going to the Alaska Writers Guild conference in Anchorage the second weekend in September. I’ll try to write a blog post about that, but I’m not sure I’ll have internet access during the meeting. I forgot to ask if the hotel has Wi-Fi.

P.S. at 5 pm. We have gusty wind, 55° F and the clouds are breaking up. I’ve put the plastic on the raised beds.

North Pole Weather 8/20/12

Sunrise this morning was at 5:56 and the sun will set at 9:50 for 15 hours 55 minutes of daylight. It is now getting quite dark at night, though we still do not have astronomical night. It won’t be long, though. Already the first leaves are turning, and it gets above 70°F only on the warmest days.

August is usually our rainiest month, but not this year. We’ve only had a quarter inch so far, and the rainiest day, Thursday, had only .12 inch. July was a little drier than average, but not to the same extent as August so far. I’ve been watering the lawn and garden – I have a well, so most of the water goes right back to the well. We even have smoke in the air — apparently there is a small forest fire, lit by lightning last spring and smoldering since,  that has flared up not that far from Fairbanks. Our fire season is normally in spring!

The zucchini is happy, and I took half a dozen to the food bank last week and still have all I can eat. I finally got caught up with the beans, and need to pick the snow peas. The beets are thriving in the holes in the cement blocks that make up the raised beds, and I’m having a beet and its greens for supper almost every night.

The beet on the right was pulled for Saturday’s supper–they were crowding each other.

Flowers? The perennials are about through for the season and setting seed. I still have some columbine blooming, and some annuals, but the annuals I planted around the raised beds have mostly been shaded out by the vegetables. For a change the lobelia have just about taken over the planter boxes with the begonias. Usually I’m lucky if one or two survive.

I’m starting to watch the weather pretty closely for frost warnings. Not right away – the extended forecast has lows in the 40’s. But August has certainly been known to produce frosts in the past, and I want to be prepared to drape plastic over the hoops on the raised beds if needed. I should get another two to three weeks of growing season, even if the trees are starting to show yellow branches, and the first fallen leaves are littering the lawn.

North Pole Weather 8/6/12

The sun rose at 5:10 this morning and will set at 10:41 this evening for 17 hours 31 minutes of daylight. It still gets no darker than nautical twilight, but the sun is a bit lower and the shadows longer at noon – the sun is now 41.6° above the horizon at its highest. We had typical fair weather Friday and Saturday – cloudy and light drizzle now and then – but Sunday was sunny and relatively warm, in the high sixties and today promises to be similar. Maybe even into the 70’s. At 7:30 am the sun is shining and the temperature is 43°F, so it’s layers for the Fair, even if I have to walk a ways to drop them off.

Notice the bolting chard.

The garden is getting farther and farther ahead of me, especially as I’m hitting the fair early each day trying to get horse photographs for my blog posts about horse color genetics. The chard is bolting, the beets need eating, the pea pods are coming faster than I can eat them, and the zucchini – well, another trip to the food bank with surplus zucchini is in order. The delphiniums are still in full bloom, way above my head, and the lilies are starting to open. Summer is winding down, but the garden is still producing like mad.

Yesterday evening.

Flash: I just got the ForeWord Clarion review for Tourist Trap. Five Star!

North Pole Weather 7/16/12

The sun rose this morning at 3:58, and will set at 11:53 this evening, for 19 hours 56 minutes of daylight. It’s only the second day this summer that the sun actually set before midnight. We’re losing about 6 ½ minutes a day, now, but it’s still civil twilight all night.

Last week was lovely weather, in the 70’s but dry—I had to water. It did rain a little last night, but only a fraction of an inch. The delphiniums are starting to bloom, and the first flowers are opening on the Maltese cross. I swear the delphiniums get taller every year; I get a crick in my neck trying to photograph them.

Tomatoes are now available at the Farmers Market. I don’t bother with those in the supermarket—they might as well be cardboard. But the local ones are vine-ripened and complement the lettuce from my garden. Cabbage, radishes, cucumbers, zucchini and onions are also in the market now, and greens of all kinds have been available for a couple of weeks. Rhubarb has been present from the start, and strawberries are also appearing. (I don’t buy them because I have a hard time keeping up with my own.) Wild berries should be available soon.

I’m off to the first day of Summer Arts Festival this morning, so that’s it until this evening. I just hope I can find a place to park. There’s a lot of construction on campus this summer, and it’s taken out almost all of the handicapped parking slots.

North Pole Weather 7/9/12

The sun rose at 3:35 this morning and will set at 12:15 tomorrow morning for 20 hours 40 minutes of daylight. We’re now losing about 6 minutes a day, and while the sun is still more than 45° above the horizon at noon, it’s dropping lower by about a tenth of a degree per day. It’s still generally warm by our standards (high 70’s) though we had a couple of days last week that didn’t quite make 70. No heavy rain, but quite a few light showers.

Two bean beds, and you can just see the peas climbing the trellis in the background.

The garden has gone from each bean and strawberry being a cause for celebration to wondering how I can keep up with it without turning vegetarian. I picked a zucchini yesterday that was over a foot long and weighed well over a pound. Thanks to the rapid growth our long days promote, it was still tender and tasty. But it is clear that I have to start checking the squash plants daily—they are already starting to shade out the lettuce in the holes around them. Peas have finally started blooming, and have shot up to the point that I need to raise the pea fence.

The squash is about to shade out the lettuce.

The delphiniums are now topping the 7’ lattice, and the first flowers are open. Still no flowers on the lilies or lynchis, but the buds have appeared on the lynchis, and two varieties of rugosa roses are in bloom. I wish sometimes that the Summer Arts Festival were sometime other than summer, but I’ve signed up again for the creative writing class. I think I’m going to have to find some neighbors who would like produce!

How Long is your Night?

Finding varieties of spinach and beets that won’t bolt. Watching the leaves turn color, even when there hasn’t yet been a frost. Trying to get last year’s Christmas cactus or poinsettia to bloom. Solving the mystery of who spilled the perfume in the meteorology lab. What do they have in common? The answer is a phenomenon called photoperiodism, which helps plants keep track of when it’s time to bloom.

Night Blooming Jasmine, right, and Kalanchoe, left.

Many plants seem to “know” how long the day is. Depending on the variety, they may refuse to bloom unless the length of day is to their liking. For varieties bred at lower latitudes, this may pose problems for Alaskans, since plants such as spinach and beets often take our long summer days as a signal that they must bloom at once rather than grow the leaves and roots we want. Similar problems arise in late summer with imported perennials, shrubs, and trees, which refuse to prepare for winter dormancy while the days are still as long as they are here in early September. But how do eyeless, clockless, plants know how long the day is?

The answer is found in a chemical, called phytochrome, produced by plants. Phytochrome changes form when red light shines on it, and slowly changes back to its original form when it is in the dark. The plant “counts” the hours of darkness by how much of the phytochrome has changed back to its dark form before it is changed again by light. The chemical’s reaction to light is very fast, so that even a short burst of light may turn all the plant’s phytochrome back to the light form, and the plant will start all over again timing how long the night is. So a plant that blooms when days are long, like spinach, is really responding to short nights, while winter-blooming plants such as poinsettias, kalanchoes, and Christmas cactus are responding to long nights. A single minute of light in the middle of the dark period is enough to “reset the clock” in some of these plants and make them think they have had two short nights (long days) instead of one long one.

Some long-night plants will bloom just as well if they are given cold nights. Many Christmas cactus are in this group. Others, like kalanchoes, will only be satisfied with long, uninterrupted, nights, which may be difficult to supply in our lighted homes. A trick that works with soybeans (and might work with winter-blooming house plants) is to place a black envelope over a single leaf near the growing point for 16 hours a day. The covered leaf makes enough of the night form of phytochrome to convince the whole plant that winter has come. If you try this with a poinsettia or kalanchoe, let me know if it works.

Some plants are even trickier in their requirements, and one of these led to the “spilled perfume” mystery. I had a night-blooming jasmine in the meteorology lab that blooms on long nights when they follow short nights. It normally has a major burst of bloom in October or November, but if someone comes in during a winter night and turns on the lights just once, that single pair of “short nights” convinces it that another summer has gone by and it blooms again about 6 weeks afterwards. The flowers are inconspicuous but have a powerful jasmine odor when they open at night. When it bloomed last year, nobody thought to mention to me that they were puzzled by the odor. It took several days before anyone could figure out where the perfume was coming from!

Author’s note: this post is recycled from one that was on the Alaska Science Forum when I was writing it in the late 80′s. I’m having a busy weekend — concert, horse show, public reading and writers’ group, and I just didn’t have time to write a new science article..