Nothing to do with climate change

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The Germantown Clopper connection seems to be one Francis C. Clopper, out of Baltimore. Mine out of John Clopper in Washington County. If conncted not demonstrable.

No idea what the real cause might be. One year we have a grerat crop, next year nothing, now you couldn't even tell we had red raspberry canes.

It has diminished the flux of those lovely but exasperating beetles that burrow into red respberries AND tomatoes JUST before you dare pick them.

Small world.

Not really - Maryland's just the center of it.

And do you believe [as in my East Coast innocence I did] that the streets of Western towns like Milwaukee [which is of course in Michigan] are full of cowboys and Amerinds?

Just for fun: Britannica 1911

I was reading this in our hard copy last night:

Changes of Climate.

Popular Belief in Climatic Change.—Belief in a change in the climate of one’s place of residence, within a few generations, and even within the memory of living men, is widespread. Evidence is constantly being brought forward of apparent climatic variations of greater or less amount which are now taking place. Thus we have many accounts of a gradual desiccation which seems to have been going on over a large region in Central Asia during historical times. In northern Africa certain ancient historical records have been taken by different writers to indicate a general decrease of rainfall during the last 3000 or more years. In his crossing of the Sahara between Algeria and the Niger, E. F. Gautier found evidence of a former large population. A gradual desiccation of the region is therefore believed to have taken place, but to-day the equatorial rain belt seems to be again advancing farther north, giving an increased rainfall. Farther south, several lakes have been reported as decreasing in size, e.g. Chad and Victoria; and wells and springs as running dry. In the Lake Chad district A. J. B. Chevalier reports the discovery of vegetable and animal remains which indicate an invasion of the Sudan by a Saharan climate. It is often held that a steady decrease in rainfall has taken place over Greece, Syria and other eastern Mediterranean lands, resulting in a gradual and inevitable deterioration and decay of their people.

What Meteorological Records show.—As concerns the popular impression regarding change of climate, it is clear at the start that no definite answer can be given on the basis of tradition or of general impression. The only answer of real value must be based on the records of accurate instruments, properly exposed and carefully read. When such instrumental records 525 are carefully examined, from the time when they were first kept, which in a few cases goes back about 150 years, there is found no good evidence of any progressive change in temperature, or in the amount of rain and snow. Even when the most accurate instrumental records are available, care must be taken to interpret them correctly. Thus, if a rainfall or snowfall record of several years at some station indicates an apparent increase or decrease in the amount of precipitation, it does not necessarily follow that this means a permanent, progressive change in climate, which is to continue indefinitely. It may simply mean that there have been a few years of somewhat more precipitation, and that a period of somewhat less precipitation is to follow.

Value of Evidence concerning Changes of Climate.—The body of facts which has been adduced as evidence of progressive changes of climate within historical times is not yet sufficiently large and complete to warrant any general correlation and study of these facts as a whole. But there are certain considerations which should be borne in mind in dealing with this evidence before any conclusions are reached. In the first place, changes in the distribution of certain fruits and cereals, and in the dates of the harvest, have often been accepted as undoubted evidence of changes in climate. Such a conclusion is by no means inevitable, for many changes in the districts of cultivation of various crops have naturally resulted from the fact that these same crops are in time found to be more profitably grown, or more easily prepared for market, in another locality. In France, C. A. Angot has made a careful compilation of the dates of the vintage from the 14th century down to the present time, and finds no support for the view so commonly held there that the climate has changed for the worse. At the present time, the average date of the grape harvest in Aubonne is exactly the same as at the close of the 16th century. After a careful study of the conditions of the date tree, from the 4th century, B.C., D. Eginitis concludes that the climate of the eastern portion of the Mediterranean basin has not changed appreciably during twenty-three centuries.

Secondly, a good many of the reports by explorers from little-known regions are contradictory. This shows the need of caution in jumping at conclusions of climatic change. An increased use of water for irrigation may cause the level of water in a lake to fall. Periodic oscillations, giving higher and then lower water, do not indicate progressive change in one direction. Many writers have seen a law in what was really a chance coincidence.

Thirdly, where a progressive desiccation seems to have taken place, it is often a question whether less rain is actually falling, or whether the inhabitants have less capacity and less energy than formerly. Is the change from a once cultivated area to a barren expanse the result of decreasing rainfall, or of the emigration of the former inhabitants to other lands? The difference between a country formerly well irrigated and fertile, and a present-day sandy, inhospitable waste may be the result of a former compulsion of the people, by a strong governing power, to till the soil and to irrigate, while now, without that compulsion, no attempt is made to keep up the work. A region of deficient rainfall, once thickly settled and prosperous, may readily become an apparently hopeless desert, even without the intervention of war and pestilence, if man allows the climate to master him. In many cases the reports of increasing dryness really concern only the decrease in the water supply from rivers and springs, and it is well known that a change in the cultivation of the soil, or in the extent of the forests, may bring about marked changes in the flow of springs and rivers without any essential change in the actual amount of rainfall.

Lastly, a region whose normal rainfall is at best barely sufficient for man’s needs may be abandoned by its inhabitants during a few years of deficient precipitation, and not again occupied even when, a few years later, normal or excessive rainfall occurs.

Periodic Oscillations of Climate: Sun-spot Period.—The discovery of a distinct eleven-year periodicity in the magnetic phenomena of the earth naturally led to investigations of similar periods in meteorology. The literature on this subject has assumed large proportions. The results, however, have not been satisfactory. The problem is difficult and obscure. Fluctuations in temperature and rainfall, occurring in an eleven-year period, have been made out for certain stations but the variations are slight, and it is not yet clear that they are sufficiently marked, uniform and persistent over large areas to make practical application of the periodicity in forecasting possible. In some cases the relation to sun-spot periodicity is open to debate; in others, the results are contradictory.

W. P. Köppen has brought forward evidence of a sun-spot period in the mean annual temperature, especially in the tropics, the maximum temperatures coming in the years of sun-spot minima. The whole amplitude of the variation in the mean annual temperatures, from sun-spot minimum to sun-spot maximum, is, however, only 1.3° in the tropics and a little less than 1° in the extra-tropics. More recently Nordmann (for the years 1870-1900) has continued Köppen’s investigation.

In 1872 C. Meldrum, then Director of the Meteorological Observatory at Mauritius, first called attention to a sun-spot periodicity in rainfall and in the frequency of tropical cyclones in the South Indian Ocean. The latter are most numerous in years of sun-spot maxima, and decrease in frequency with the approach of sun-spot minima. Poëy found later a similar relation in the case of the West Indian hurricanes. Meldrum’s conclusions regarding rainfall were that, with few exceptions, there is more rain in years of sun-spot maxima. S. A. Hill found it to be true of the Indian summer monsoon rains that there seems to be an excess in the first half of the cycle, after the sun-spot maximum. The winter rains of northern India, however, show the opposite relation; the minimum following, or coinciding with, the sun-spot maximum. Particular attention has been paid to the sun-spot cycle of rainfall in India, because of the close relation between famines and the summer monsoon rainfall in that country. Sir Norman Lockyer and Dr W. J. S. Lockyer have recently studied the variations of rainfall in the region surrounding the Indian Ocean in the light of solar changes in temperature. They find that India has two pulses of rainfall, one near the maximum and the other near the minimum of the sun-spot period. The famines of the last fifty years have occurred in the intervals between these two pulses, and these writers believe that if as much had been known in 1836 as is now known, the probability of famines at all the subsequent dates might have been foreseen.

Relations between the sun-spot period and various other meteorological phenomena than temperature, rainfall and tropical cyclones have been made the subject of numerous investigations, but on the whole the results are still too uncertain to be of any but a theoretical value. Some promising conclusions seem, however, to have been reached in regard to pressure variations, and their control over other climatic elements.

Brückner’s 35-Year Cycle.—Of more importance than the results thus far reached for the sun-spot period are those which clearly establish a somewhat longer period of slight fluctuations or oscillations of climate, known as the Brückner cycle, after Professor Brückner of Bern, who has made a careful investigation of the whole subject of climatic changes and finds evidence of a 35-year periodicity in temperature and rainfall. In a cycle whose average length is 35 years, there comes a series of years which are somewhat cooler and also more rainy, and then a series of years which are somewhat warmer and drier. The interval in some cases is twenty years; in others it is fifty. The average interval between two cool and moist, or warm and dry, periods is about 35 years. The mean amplitude of the temperature fluctuation, based on large numbers of data, is a little less than 2°. The fluctuations in rainfall are more marked in interiors than on coasts. The general mean amplitude is 12%, or, excluding exceptional districts, 24%. Regions whose normal rainfall is small are most affected.

The following table shows the dates and characters of Brückner’s periods:—
Warm 1746-1755 1791-1805 1821-1835 1851-1870 ..
Dry 1756-1770 1781-1805 1826-1840 1856-1870 ..
Cold 1731-1745 1756-1790 1806-1820 1836-1850 1871-1885
Wet 1736-1755 1771-1780 1806-1825 1841-1855 1871-1885

526

Interesting confirmation of Brückner’s 35-year period has been found by E. Richter in the variations of the Swiss glaciers, but as these glaciers differ in length, they do not all advance and retreat at the same time. The advance is seen during the cold and damp periods. Brückner has found certain districts in which the phases and epochs of the climatic cycle are exactly reversed. These exceptional districts are almost altogether limited to marine climates. There is thus a sort of compensation between oceans and continents. The rainier periods on the continents are accompanied by relatively low pressures, while the pressures are high and the period dry over the oceans and vice versa. The cold and rainy periods are also marked by a decrease in all pressure differences. It is obvious that changes in the general distribution of atmospheric pressures, over extended areas, are closely associated with fluctuations in temperature and rainfall. These changes in pressure distribution must in some way be associated with changes in the general circulation of the atmosphere, and these again must depend upon some external controlling cause or causes. W. J. S. Lockyer has called attention to the fact that there seems to be a periodicity of about 35 years in solar activity, and that this corresponds with the Brückner period.

It is clear that the existence of a 35-year period will account for many of the views that have been advanced in favour of a progressive change of climate. A succession of a few years wetter or drier than the normal is likely to lead to the conclusion that the change is permanent. Accurate observations extending over as many years as possible, and discussed without prejudice, are necessary before any conclusions are drawn. Observations for one station during the wetter part of a cycle should not be compared with observations for another station during the drier part of the same, or of another cycle.

There are evidences of longer climatic cycles than eleven or 35 years. Brückner calls attention to the fact that sometimes two of his periods seem to merge into one. E. Richter shows much the same thing for the Alpine glaciers. Evidence of considerable climatic changes since the last glacial period is not lacking. But as yet nothing sufficiently definite to warrant general conclusions has been brought forward.

Geological Changes in Climate.—Changes of climate in the geological past are known with absolute certainty to have taken place: periods of glacial invasion, as well as periods of more genial conditions. The evidence, and the causes of these changes have been discussed and re-discussed, by writers almost without number, and from all points of view. Changes in the intensity of insolation; in the sun itself; in the conditions of the earth’s atmosphere; in the astronomical relations of earth and sun; in the distribution of land and water; in the position of the earth’s axis; in the altitude of the land; in the presence of volcanic dust;—now cosmic, now terrestrial conditions—have been suggested, combated, put forward again. None of these hypotheses has prevailed in preference to others. No actual proof of the correctness of this or that theory has been brought forward. No general agreement has been reached.

Conclusion.—Without denying the possibility, or even the probability, of the establishment of the fact of secular changes, there is as yet no sufficient warrant for believing in considerable permanent changes over large areas. Dufour, after a thorough study of all available evidence, has concluded that a change of climate has not been proved. There are periodic oscillations of slight amount. A 35-year period is fairly well established, but is nevertheless of considerable irregularity, and cannot as yet be practically applied in forecasting. Longer periods are suggested, but not made out. As to causes, variations in solar activity are naturally receiving attention, and the results thus far are promising. But climate is a great complex, and complete and satisfactory explanations of all the facts will be difficult, perhaps impossible, to reach. At present, indeed, the facts which call for explanation are still in most cases but poorly determined, and the processes at work are insufficiently understood. Climate is not absolutely a constant. The pendulum swings to the right and to the left. And its swing is as far to the right as to the left. Each generation lives through a part of one, or two, or even three oscillations. A snapshot view of these oscillations makes them seem permanent. As Supan has well said, it was formerly believed that climate changes locally, but progressively and permanently. It is now believed that oscillations of climate are limited in time, but occur over wide areas.
Literature.—Scientific climatology is based upon numerical results, obtained by systematic, long continued, accurate meteorological observations. The essential part of its literature is therefore found in the collections of data published by the various meteorological services. The only comprehensive text-book of climatology is the Handbuch der Klimatologie of Professor Julius Hann, of the university of Vienna (Stuttgart, 1897). This is the standard book on the subject, and upon it is based much of the present article, and of other recent discussions of climate. The first volume deals with general climatology, and has been translated into English (London and New York, 1903). Reference should be made to this book for further details than are here given. The second and third volumes are devoted to the climates of the different countries of the world. Woeikof’s Die Klimate der Erde (Jena, 1887) is also a valuable reference book. The standard meteorological journal of the world, the Meteorologische Zeitschrift (Braunschweig, monthly), is indispensable to any one who wishes to keep in touch with the latest publications. The Quarterly Journal of the Royal Meteorological Society (London), Symons’s Monthly Meteorological Magazine (London), and the Monthly Weather Review (Washington, D.C.) are also valuable. The newest and most complete collection of charts is that in the Atlas of Meteorology (London, 1899), in which also there is an excellent working bibliography. For the titles of more recent publications reference may be made to the International Catalogue of Scientific Literature (Meteorology).
(R. De C. W.)

tl;dr...

Cliff's notes?

No, just the climate change section of the climate and climatology article in the allegedly classic 1911 edition Encyclopaedia Britannica, which though in places outmoded includes some useful stuff more modern sources find irrelevant and also shed light on HOW understanding does / does not change.

I have it hard copy because my parents had it [whether because it was classic or because the price was not, do not ask me, I was not consulted azt the time of purchase about 1960] and as Number 1 Son I grabbed it when the household goods and gods were dispersed.

IF you have a few minutes and are so inclined, you might find a gaze through of interest. If not no big deal, 1911 will not mind.

I found it interesting that at least in that article I found no mention of the CO2 factor. I am almost positive - NOW I am going to have to check - not your fault THIS time] that in another inherited text, in this case from the 20s - the one proclaiming the authenticity of Piltdown Man - CO2 IS put forward as a heating mechanism. I know it was in place by the time I was reading about such stuff.