Many Japanese, in fact, are firmly convinced that only in Japan are there four distinct seasons, each one adorned in its own unique range of cosmetics and accessories. Spring flaunts itself with flowering cherries, summer parades green rice plants to the sound of cicadas and nightingales, autumn dazzles with shocking reds, yellows and purples, and winter slinks in under a mantle of snow, ending in a surprise flourish of early plum blossoms before the frosts have gone.
Foreigners are not expected to have the appropriate feelings about seasonal changes, since foreign countries are not thought to have the same rhythms of nature. (This notion may be reinforced by Japanese holidaymakers' overwhelming preference for the tropical resorts of Hawaii and South East Asia, where the seasons are not as pronounced as in temperate climes.)
But there is no doubt that in Japan considerable energy is invested in ensuring one gets the required dose of rising sap or autumnal melancholy, at the right time. Close to my house is Aoyama graveyard, which is renowned for its cherry blossoms. It is the biggest graveyard in Tokyo, and during the first two weekends of April it is standing room only. Every weekday evening thousands of office workers converge with plastic boxes of food, cans of beer and even portable karaoke recorders to toast the blossoms by the light of the moon, an electric torch, or a cigarette lighter. Most become so absorbed in their mystical experience that they forget to take their rubbish home with them.
It is, of course, important to know when the cherry blossoms are flowering when planning such an outing, and rather than trust one's own eyes, it is infinitely more reliable to telephone the Observation Department of the Applied Meteorological Division of the Japan Meterological Agency. The agency measures seasonal changes of a number of plants and animals from its 102 observation offices around the country.
A visit to the Tokyo headquarters of the agency's Observation Department revealed just how seriously they deal with the changing seasons. Computer print-outs were obligingly produced, showing that the cherry blossom arrived on 31 March, two days late, in Tokyo this year compared to a 30-year average, and has varied from an early showing in 1966 on 20 March, to a disturbingly late appearance in 1984 when the buds did not start opening until 11 April.
Apart from the cherry blossom - to those of us who take these things seriously, the Prunus yedoensis matsum, as opposed to other varieties of cherry - the Observation Department monitors plum, camellia, dandelion, azalea, wistaria, hydrangea, crape-myrtle, pampas grass, gingko and maple. The animals that are watched for are the skylark, nightingale, swallow, two kinds of butterfly, leopard frog, dragonfly, firefly, two kinds of cicada and the shrike.
The guidelines for a 'sighting' are very strict. Each of the provincial observation offices has two people assigned to monitor the 23 varieties of plants and animals, within a pre-ordained circumference of the office. They must see, or hear, the emerging blossom, bird-song or butterfly themselves. A friend's word does not satisfy the official criteria.
However, according to Kazunobu Nakamura, the deputy director of the Observation Department, their scientific rigour is being undermined by natural forces out of their control. In fact, Mr Nakamura's department is facing a minor crisis. The indicators are disappearing under the encroaching cement, Tarmac and insecticides of modern Japan. Many of the observation stations now do not have enough unspoilt countryside in their vicinity to observe the seasonal indicators. Japan is killing off its own seasons.
Worst hit are the leopard frogs: of the 102 observatories, 69 were unable to find sight or sound of the frog last year. Fireflies were absent from 50 stations. Also in steep decline were dragonflies, cicadas and shrikes. Bush clover was the worst affected plant, not appearing at 30 locations.
The Meterological Agency, of course, has no power to cut industrial or agricultural polution, nor can it protect forests or meadows. So it is doing the next best thing: it is changing the list. 'Our main problems are with the animals,' said Mr Nakamura. When a consensus has been reached by the observatories on what species to exclude or include the department will be able to issue comprehensive natural signposts for seasonal change. Until then, for those of us in Japan living outside the range of the firefly, and with no bush clover or pampas grass growing near by, the passing of the seasons can only be guessed at.