Thursday 27 February 2020

Climate Change in Ottawa: 30-Year Report

I have lived in the Ottawa region for 34 years, now. I have always had more than a passing interest in the weather and meteorology. Let's combine the two, and see what comes out.

1. It's Getting Warmer

Over 30 years, the weather in Ottawa has gradually grown warmer, especially in Winter.

Anecdotal Evidence:
In the Eighties, temperatures frequently ventured down into the minus-thirties. News stories abounded, showing steam plumes off of every building, and people freezing through daytime highs in the mid-minus-twenties.

Now? It doesn't happen. Oh, once every few years, you'll get a low temperature in the minus-thirty range; but only one, and only once per winter. Generally, the lowest the temperature gets nowadays, in an average winter, is about -26.

Direct Evidence:
If you graph the daily temperature records for the year, against the dates they were set, a remarkable pattern emerges: again, especially in Winter, the low-temperature records were generally set years ago--decades ago--while the high-temperature records have been set in the past few years. It's really quite striking, when viewed in this way, and delivers an unambiguous argument that the climate is warming.

The Rideau Canal: In the eighties, it often opened in late-December; and skating generally lasted into mid-March. In recent years, it almost never opens before mid-January, almost always closes by late February; and this year, for the first time, not all sections of the Canal were opened. It's a trend.

Winterlude: Ottawa's famous winter festival is at risk of busting. In the past, the carnival was a 10-day event in mid-January. But it kept running into the January thaw. So they broke it up into three weekends, and ran it mid-February. Problem is, in recent years, there's often a meltdown mid-event. Our winters eventually will become too inconsistent to hold a major winter carnival, at all. I expect that to happen in the next 20-30 years. I also expect still to be talking about it at that point.

2. Winters are Getting Shorter

That's a process that seems to have accelerated somewhat in recent years.

I can only offer anecdotal evidence for this one. In the eighties, winter was usually well underway by mid-December. The snow often began falling in early November. I remember one winter, in the early nineties, when we didn't get a major snowfall, and the Canal didn't freeze, until late November.

Contrast that with today, when the Canal is often still unfrozen into mid-December; and often the first major snowfall now occurs in that month, too.

Yep; it's changing. Only an idiot can still murmur about natural processes, at this point.

Have a warm one,

-Bill

Friday 21 February 2020

700! A DX'er Exults

As regular readers of this column may be aware, I have been DX'ing since 1975; or, for 45 years. I've been doing it in the Ottawa area for the past 34.

As you also may know, DX'ing is the attempt to receive radio stations over long distances. In my case, I chose to focus on AM radio.

As of this morning, I have now logged 700 distinct stations, from this area.

Putting it into perspective: there are approximately 120 AM frequencies available. This means that I've received, on average, almost six stations for every frequency. On only one or two frequencies have I never been able to log more than one station; and for some (the so-called graveyard channels), the total is close to 15.

I consider a 'distinct station' to be one that is identifiable by its frequency, callsign, and location. On the rare occasion that a station changes its callsign or frequency, then when I hear it again, I'll record it as a new station. If a station changes location, I generally ignore it, unless they switch transmitting locations (very rare, indeed).

Over the years, there have been many changes in the hobby. Audibly, in some cases; Canadian AM stations are largely switching to FM, and as a consequence French is disappearing from the band. At the same time, Spanish is increasingly heard from US stations.

The old clear-channel frequencies are slowly filling up. There are stations in Texas, for example, which I haven't heard since the eighties. My average distance per station has been steadily dropping.

In the Nineties, the expanded AM band (1610-1700 KHz) opened up, and there was a rash of loggings from low-powered travel information stations. Some of them were just jaw-dropping; a TIS from an airport in Dallas-Fort Worth, Texas, for example, running at most 10 Watts, with a daytime reach of maybe a kilometre. (For reference, I've logged the airport TIS in Ottawa--barely more than ten kilometres away, and operating at the same Wattage--only twice.)

Over all of those years, my greatest catch remains Vatican Radio, on 1611 KHz, in the late-nineties. That's a good third of the way around the world.

The ways you can identify a station have also evolved. Whereas, in the past, identifying a station took place primarily with the aid of printed references, which quickly run out-of-date, today we have the Internet. Vast numbers of stations can be heard in near-real time, thanks to streaming; and numerous Internet-based references exist.

There are many tricks I've employed over the years; the old canner-lid trick, to block strong signals from one direction, allowing fainter signals from another direction to trickle through; it's how I logged 1070 KNX, Los Angeles, from the West Coast, in the null of local station CFAX, in Victoria. I've used numerous loop antennas, the occasional longwire (in an urban environment, that's usually tricky, and potentially very noisy). I'll often tune one or two kilohertz away from a frequency, to better eliminate adjacent-channel interference. I'll play with the bass and treble controls, or audio bandwidth, to optimize for the voice I'm hearing.

The biggest factor, overall has been persistence. In the Fall, when the sun returns to setting early enough to make DX'ing worthwhile again, it takes me a couple of weeks really to get familiar with my station listings again. From then, until late Spring, I know my stations well, which makes it much easier to identify a station on the fly--and much easier to spot something that 'doesn't belong'. If you DX only occasionally, you'll constantly be asking yourself, "What's that station?"

That's my two cents' worth at 700. I'll chime in again about it when I reach 1,000. That'll be in ten or fifteen years.

Until then, be well. ;)

-Bill