The next graph of temperature from the ice core for the last 10,000 years (the current interglacial period) shows that Greenland is now colder than for most of that period (vertical scale in degrees C below zero). The following graphs have a time scale in years Before Present (BP). I sometimes see graphs of ice-core temperatures or greenhouse gasses that are based on measurements every 1,000 or 2,000 years: not nearly close enough together for comparisons that are useful today. I downloaded and graphed these data in Excel myself. This data set is useful because it reports temperatures (measured by oxygen isotopes) every 10 to 60 years - a good resolution. The US government drilled the GISP 2 ice core in central Greenland over a five-year period, and the data is available here. Annual layering in undisturbed glacial ice allows us to precisely date the layers, and gives us a very accurate time and temperature sequence. Paleotemperature data from ice cores is considered to be our best continuous record of temperatures on the planet for time-spans up to about 420,000 years ago. To detail the more recent prehistoric temperature changes, scientists have drilled a number of ice cores in ancient glacial ice. Rohde / Global Warming Art The last 10 millenia With so much volatility in the graphs, anyone could play “pick a trend” and depending on which dot you start from, you can get any trend you want. The dinosaurs would have scoffed at us: “What? You think this is warm?” vanished, it’s been one long slide down the thermometer, and our current “record heatwave” is far cooler than normal. But, in terms of homo sapiens civilization, things are cooler than usual, and appear to be cooling. What’s obvious is that in terms of homo sapiens history, things are warm now (because we’re not in an ice age). We start with the whole 65 million years, then zoom in, and zoom in again to the last 12,000 from both ends of the world. If you wonder where today’s temperature fits in with the grand scheme of time on Earth since the dinosaurs were wiped out, here’s the history. Are we headed for an ice age? (See below for more detail.)ĭavid Lappi is a geologist from Alaska who has sent in a set of beautiful graphs–including an especially prosaic one of the last 10,000 years in Greenland–that he put together himself (and which I’ve copied here at the top). Greenland Interglacial Temperatures – last 10,000 years. Get Laughs, Get Attention, Get Your Message Across.The Wong Fielding Meeting on Global Warming - Documents.Odour reduction practices at Narrogin Beef Producers.Western Australian State Government email list.Australian Elected Representatives – Emails and phones.Thermometer selection (mystery loss of data).The 800 year lag in CO2 after temperature – graphed.ClimateGate: Thirty Years in the Making (Edition 1.1).The evidence that AGW fans need to provide.
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