RECORD KEEPING. Elizabeth Losey, a now-retired field biologist, kept records of bird arrival at Seney National Wildlife Refuge, Michigan for fifty years. Recently, Terry Root, an ornithologist of Michigan University, correlated regional temperature records, which showed a consistent warming trend, with Losey's findings; the results showed current arrival times for many birds that are up to three weeks earlier than fifty years ago.

BIRD MIGRATION. England's long history of nature observation makes it a center of phenology, the study of how natural cycles, such as flower blooming and bird nesting, are affected by seasonal and other environmental changes. In Britain and all across Europe, detailed records show that rising average temperatures are affecting natural processes. David Walker of the Dungeness Bird Observatory holds a chiffchaff Phylloscopus collybita, a warbler whose yearly migration and nesting are much earlier now than in the mid-20th century. North of the observatory, in Poole Harbor, little egrets have begun nesting at the wildlife refuge on Brownsea Island. This secretive wading bird, common in more southern Europe, has been infrequent in Britain until recent years.

EARLY BUDS. One of the most dramatic changes within the British countryside is the earlier budding of the famous English oaks, Quercus robur. These trees are monitored on a canopy walkway at Wytham Environmental Change Network. From across Europe, 30 years of botanical gardens' records show that the growing season is almost 11 days longer due to earlier spring and later fall events.

EARLY EGGS. Ornithologist Andrew Gosler of Oxford University records the date of egg laying of great tits Parus major, in Wytham Wood. Monitoring 900 nestboxes since the 1960s, he has documented a three-week advance in date of first laying, which is "entirely consistent with the weather." British Trust for Ornithology records confirm similar advances for many other birds.

MATING CLOCKS. The common frog Rana edulis has been shown to be mating several weeks earlier according to studies by UK biologist Trevor Beebee, in Sussex, UK. And at the famous British Agricultural Station at Rothhamsted north of London, old records of insect abundance and range are being compared with current collections. This scientist studies moths such as the common footman whose earlier flight times appear to correlate to the warmer temperatures across Britain.

BLOOMING CONFUSION. Throughout the temperate zone, records detail changes in where and when plants bloom and thrive. One recent study reviewed National Arboretum records on the spring bloom time of 100 common Washington D.C. area plants. Eighty-nine of the 100 showed significantly earlier blooming. This one, the common lawn weed deadnettle, is blooming an average of 39 days earlier than in 1970.

SMOG. Aerial view of Chicago, Illinois during August of 1995 when a heat wave killed 500 people. One of the consequences of heating in the atmosphere is more instability in local weather -- hotter summers, deeper droughts, sharp changes in seasonal weather patterns, much heavier downpours during rainstorms.

24 HOURS LATER: Prospect Park, Brooklyn, NY, experiences a rapid weather change: daffodils bask in 70 degree temperatures one April day and the next are buried under four inches of snow. Such freak changes, although not indicative themselves of a climate change, are predicted to occur more often as the atmosphere warms.

24 HOURS LATER: Prospect Park, Brooklyn, NY, experiences a rapid weather change: daffodils bask in 70 degree temperatures one April day and the next are buried under four inches of snow. Such freak changes, although not indicative themselves of a climate change, are predicted to occur more often as the atmosphere warms.