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This presentation explores the scientific evidence supporting the prediction of global cooling over the next 25 years. It analyzes ice core isotope data, sea surface temperature changes, glacial fluctuations, solar variations, and historic measurements to understand past climate changes and make predictions for the future.
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Scientific evidence for predicting 25 years of global cooling: Ice core isotope data, decadal sea surface temperature changes, glacial fluctuations, solar variations, and historic measurements— the past is the key to the future Don J Easterbrook Dept of Geology, Western Wash Univ. Bellingham, WA
IPCC, NASA Predictions Global warming isn’t a prediction. It is happening “If Canada proceeds, and we do nothing, it will be game over for the climate. ….concentrations of carbon …..would reach levels higher than in the Pliocene era, more than 2.5 million years ago, when sea level was at least 50 feet higher. …assure that the disintegration of the ice sheets would accelerate out of control.Sea levels would rise and destroy coastal cities. Global temperatures would become intolerable. Twenty to 50 percent of the planet’s species would be driven to extinction. Civilization would be at risk.. Over the next several decades, the …region from North Dakota to Texas will develop semi-permanent drought, with rain,… occurring in extreme events with heavy flooding. Economic losses would be incalculable. .the Midwest would be a dust bowl. California’s Central Valley could no longer be irrigated. Food prices would rise to unprecedented levels. If this sounds apocalyptic, it is. (James Hansen, NY Times editiorial, 2012)
OR . . . . . . • “Global warming is over“ (Easterbrook, 2000, 2010) • “The current warm cycle should end in the next few years, and global warming should abate, rather than increase, in the coming decades.” (Easterbrook, 2000) • “The current warm cycle should end soon and global temperatures should cool.”(Easterbrook, 2000)
WARMING OR COOLING? • What is happening now—warming or cooling? • How have climates changed in the past? • What is the basis for predicting future climate? • What is in store for the next 25 years?
Winters in the US have been much cooler than usual during the past decade
How do you predict climate? • Computer models • Real physical evidence to establish cyclical patterns In order to predict where we are heading, we need to know where we’ve been. The past is the key to the future (Cartoons by Josh)
Measuring climatic warming/cooling in the geologic past • Historic temperature measurements • Oxygen isotope ratios in deep ice cores. • Advance and retreat of glaciers. • Measurement of ocean temperatures Data in this presentation may be found in this volume
Climate during the past century The historical record: Two periods of global warming and 3 periods of global cooling have occurred in the past century,
Climate during the past 10,000 years The Greenland GISP2 ice core • The ratio of 18O to 16O depends on the temperature at the time snow crystals formed in the atmosphere. The oxygen isotopic composition of a sample is expressed as a departure of the 18O/16O ratio from a standard. • δ18O = (18O/16O)sample‒ (18O/16O) _________________________________ x 103 (18O/16O)standard • where δ18Ois the of ratio 18O/16O expressed as per mil (0/00) • The GISP2 isotope data reflects Greenland temperatures but excellent correlation with global glacier fluctuations makes it a good proxy for global temperatures.
40 periods of warming and cooling in the past 500 years shown by isotope data from Greenland ice cores with an average span of 27 years
The Medieval Warm Period and Little Ice Age were global climate events~3,000 publications including many books (Loehle, 2007) Mann et al. (1998)
Almost every alpine glacier in the world shows Little Ice Age expansion of ice following the Medieval Warmer Period
Abrupt temp changes of 8-24°F/100 yrs have occurred many times in the past 15,000 years
Abrupt, intense periods of global warming 10-15,000years ago
Global warming/cooling in past 25,000 years • Global warming has occurred many times in the last 25,000 years, all caused by natural, recurring processes. • The magnitude and intensity of global warming during the past century is insignificant compared to the magnitude and intensity of the profound natural climate reversals over the past 25,000 years,
Conclusions about global warming from the past few centuries to 25,000 years ago • Global warming has occurred many times in the last 25,000 years, caused by natural, recurring processes. • The magnitude and intensity of global warming during the past century are insignificant compared to the magnitude and intensity of the profound natural climate reversals over the past 15,000 years. • Period of global warming and cooling show a regular, systematic pattern. • These intense periods of global warming occurred long before any possible effect of atmospheric CO2.
What causes the systematic pattern of global warming and cooling? • Relationship of climate change and sea surface temperature—the PDO and AMO
Glacier fluctuations are a direct result of changes in the PDO Glacier fluctuations exactly match the Pacific Decadal Oscillation (PDO) and global temperature changes
GLACIER FLUCTUATIONS CLIMATE CHANGES PDO-AMO MODE CHANGES WHAT DRIVES PDO-AMO MODES?
Sea surface temperatures 1997 2001 1999 2007
March, 2009 May 2012 Cold PDO has been firmly entrenched since 1999
Good correlation between North Atlantic SST and temperatures of European rural areas
Good correlation between AMO and advance and retreat of Swiss glaciers
Setting up of the PDO cold phase assures global cooling for the next ~25-30 years.
How cool will it get? 1, Like 1945-1977 2. Like 1880-1915 3. Like 1790-1820 Dalton Minimum 4. Like 1650-1700 Maunder Minimum
Dalton Solar Minimum (1790-1820) Napoleon’s army of 400,000 reduced to 40,000, largely by the harshness of the 1812 Russian winter during the Dalton Minimum
Global cooling occurs during times of few sunspots and low solar irradiance
Correlation between solar activity and climateChange in production rate of radiocarbon and temperature
Svensmark, CERN experiments • Variations in the sun’s magnetic field affects cosmic radiation received by the Earth. • Cosmic rays produce ions that act as seeds of condensation (clouds). • Increased cloudiness results in climatic cooling.
CONCLUSIONS • Many periods of natural warming and cooling have occurred in the past 15,000 years, long before CO2 could have caused them. • More than 40 periods of global warming/cooling have occurred in the past 500 years, none of which could have been caused by CO2. • Many periods of far more intense warming have occurred from natural causes in the past 15,000 years, some as great as 20°F in 40 years. • Almost all of the past 10,000 years has been warmerthan present. • The Medieval Warm Period and Little Ice Age did occur—the ‘hockey stick’ is a bad joke. • The climate has been warming gradually since the Little Ice Age began about 500 years ago. • Recurring patterns of cyclic global climate change form a reliable basis for predicting future climate changes—the past is the key to the future. • Computer models have failed badly in predicting temperatures.
Climate changes result from changes in the PDO and AMO. • The PDO flipped from cool to warm in 1977 and climate warmed; the PDO flipped from warm to cool in 1999 and climate cooled. • Changes in ocean temperatures correlate well with solar changes. • Changes in the solar magnetic field affect incidence of cosmic rays on Earth. Changes in cosmic ray intensity affects cloudiness, which affects global temperatures. • The sun is now in a solar minimum and seems to be heading for the Dalton Minimum (1790-1820), during which global temperatures declined sharply. • The 1977-1998 global warming period is over and we are now in a period of global cooling that will last several decades, similar to continuing natural cycles dating back thousands of years.
Global cooling is real Not only is the prediction of cooling in the decades ahead based on solid scientific data, but the data indicate it is a virtual certainty. Cooling in the coming decades is assured but the question remains—how cool will it be?
By 2040, (in 28 yrs), the population will be twice what it is today.By 2080 (in 68 yrs), the population will be 4 times what it I now.Global cooling, will reduce food production and the demand for energy will increase dramatically
Dogma is an impediment to the free exercise of thought. It paralyses the intelligence. Conclusions based upon preconceived ideas are valueless. It is only the open mind that really thinks.Patricia Wentworth, 1949 For data and information go to: Bing.com or Google.com and enter Don Easterbrook global warming