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MWP And LIA In IPCC Reports
The description of the Medieval Warm Period and Little Ice Age in IPCC reports has changed since the first report in 1990 as scientific understanding of the temperature record of the past 1000 years has improved. The Medieval Warm Period (MWP) and Little Ice Age (LIA) are the best-known temperature fluctuations in the last millennium. Critics of the "hockey stick graph" of all subsequent reports have claimed that the record of the MWP and LIA were suppressed in the IPCC Third Assessment Report although every report discussed the phenomena. 1990 report (FAR) With the growth of interest in global warming in the 1980s came renewed interest in the past temperature record as well as the question of whether past times had been warmer or colder than "present". However, available records were then few. In Chapter 7 "Observed Climate Variations and Change", the Executive Summary on page 199 noted that palaeo-climatic evidence indicated surface temperature "fluctuations including the Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1000 Year Temperature Comparison
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest positive integer. It is also sometimes considered the first of the infinite sequence of natural numbers, followed by 2, although by other definitions 1 is the second natural number, following 0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally accepted until the mid-20th century. Additionally, 1 is the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperature Record Of The Past 1000 Years
The temperature record of the last 2,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional: the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that "Average Northern Hemisphere temperatures during the second half of the 20th century were ''very likely'' higher than during any other 50-year period in the last 500 years and ''likely'' the highest in at least the past 1,300 years." The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century. As of 2010 this broad pattern was supported by more than two dozen reconstructions, using various statistical methods and combinations o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medieval Warm Period
The Medieval Warm Period (MWP), also known as the Medieval Climate Optimum or the Medieval Climatic Anomaly, was a time of warm climate in the North Atlantic region that lasted from to . Proxy (climate), Climate proxy records show peak warmth occurred at different times for different regions, which indicate that the MWP was not a globally uniform event. Some refer to the MWP as the ''Medieval Climatic Anomaly'' to emphasize that climatic effects other than temperature were also important. The MWP was followed by a regionally cooler period in the North Atlantic and elsewhere, which is sometimes called the Little Ice Age, Little Ice Age (LIA). Possible causes of the MWP include increased solar activity, decreased volcanic activity, and changes in ocean circulation. Research The Medieval Warm Period (MWP) is generally thought to have occurred from –, during the European Middle Ages. In 1965, Hubert Lamb, one of the first paleoclimatologists, published research based on data from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little Ice Age
The Little Ice Age (LIA) was a period of regional cooling, particularly pronounced in the North Atlantic region. It was not a true ice age of global extent. The term was introduced into scientific literature by François E. Matthes in 1939. Matthes described glaciers in the Sierra Nevada of California that he believed could not have survived the hypsithermal; his usage of "Little Ice Age" has been superseded by "Neoglaciation". The period has been conventionally defined as extending from the 16th to the 19th centuries, (noted in Grove 2004:4). but some experts prefer an alternative timespan from about 1300 to about 1850. The NASA Earth Observatory notes three particularly cold intervals. One began about 1650, another about 1770, and the last in 1850, all of which were separated by intervals of slight warming. The Intergovernmental Panel on Climate Change Third Assessment Report considered that the timing and the areas affected by the Little Ice Age suggested largely independent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hockey Stick Graph (global Temperature)
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures. The term ''hockey stick graph'' was popularized by the climatologist Jerry Mahlman, to describe the pattern shown by the (MBH99) reconstruction, envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick's "shaft" followed by a sharp, steady increase corresponding to the "blade" portion. The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPCC Third Assessment Report
The IPCC Third Assessment Report (TAR), ''Climate Change 2001'', is an assessment of available scientific and socio-economic information on climate change by the IPCC. Statements of the IPCC or information from the TAR are often used as a reference showing a scientific consensus on the subject of global warming, although a small minority of scientists take issue with the UN assessments (see also Global warming controversy and Politics of global warming). The Third Assessment Report (TAR) was completed in 2001 and consists of four reports, three of them from its Working Groups: Working Group I: The Scientific Basis;TAR Working Group 1 IPCC. Working Group II: Impacts, Adaptation and Vulnerability;TAR Working ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Warming
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPCC First Assessment Report
The First Assessment Report (FAR) of the Intergovernmental Panel on Climate Change (IPCC) was completed in 1990. It served as the basis of the United Nations Framework Convention on Climate Change (UNFCCC). This report had effects not only on the establishment of the United Nations Framework Convention on Climate Change (UNFCCC), but also on the first conference of the parties (COP), held in Berlin in 1995. The executive summary of the WG I Summary for Policymakers report said they are certain that emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases, resulting on average in an additional warming of the Earth's surface. They calculated with confidence that CO2 had been responsible for over half the enhanced greenhouse effect. They predicted that under a "business as usual" (BAU) scenario, global mean temperature would increase by about 0.3 °C per decade during the 1stcentury. They judged that globa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phil Jones (climatologist)
Philip Douglas Jones (born 22 April 1952) is a former director of the Climatic Research Unit (CRU) and a professor in the School of Environmental Sciences at the University of East Anglia (UEA) from 1998, having begun his career at the unit in 1976. He retired from these positions at the end of 2016, and was replaced as CRU director by Tim Osborn. Jones then took up a position as a Professorial Fellow at the UEA from January 2017. His research interests include instrumental climate change, palaeoclimatology, detection of climate change and the extension of riverflow records in the UK. He has also published papers on the temperature record of the past 1000 years. He is known for maintaining a time series of the instrumental temperature record. This work was featured prominently in both the 2001 and 2007 IPCC reports, where he was a contributing author to Chapter 12, ''Detection of Climate Change and Attribution of Causes'', of the Third Assessment Report and a Coordinating Lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keith Briffa
Keith Raphael Briffa (27 December 1952 – 29 October 2017) was a climatologist and deputy director of the Climatic Research Unit. He authored or co-authored over 130 scholarly articles, chapters and books. In his professional work, he focused on climate variability in the late Holocene, with a special focus on northern portions of Europe and Asia. Briffa's preferred method was dendroclimatology, which is a set of procedures intended to decode information about the past climate from tree rings. Briffa helped develop data sets from trees from Canada, Fennoscandia, and northern Siberia which have been used in climate research. Briffa grew up in Speke, and attended St Francis Xavier's College, Liverpool. He studied biological sciences at the University of East Anglia. He completed his PhD at the University of East Anglia entitled ''"Tree-climate relationships and dendroclimatological reconstruction in British Isles"'' in 1984. From 1994 to 2000, Briffa served on the scientific steeri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubert Lamb
Hubert Horace Lamb (22 September 1913 in Bedford – 28 June 1997 in Holt, Norfolk, Holt, Norfolk) was an English climatologist who founded the Climatic Research Unit in 1972 in the School of Environmental Sciences at the University of East Anglia. Career Most of Lamb's scientific life was spent at the Met Office, Meteorological Office, UK, where he started as a Technical Officer progressing by special merit promotion. As a Quaker and conscientious objector, Lamb refused to work on the meteorology of gas spraying during World War II, and was transferred to the Irish Meteorological Service, then still closely associated with the UK Met Office. On returning to the UK service after the war his responsibilities were in the fields of long range weather forecasting, world climatology and climate change. In this capacity he was assigned to West Germany and Malta. Earlier he was also posted as meteorological adviser on a Norwegian whaling factory ship to Antarctica. He became a Membe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central England Temperature
The Central England Temperature (CET) record is a meteorological dataset originally published by Professor Gordon Manley in 1953 and subsequently extended and updated in 1974, following many decades of painstaking work. The monthly mean surface air temperatures, for the Midlands region of England, are given (in degrees Celsius) from the year 1659 to the present. This record represents the longest series of monthly temperature observations in existence. It is a valuable dataset for meteorologists and climate scientists. It is monthly from 1659, and a daily version has been produced from 1772. The monthly means from November 1722 onwards are given to a precision of 0.1 °C. The earliest years of the series, from 1659 to October 1722 inclusive, for the most part only have monthly means given to the nearest degree or half a degree, though there is a small 'window' of 0.1 degree precision from 1699 to 1706 inclusive. This reflects the number, accuracy, reliability and geographical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
