With the addition of the "Cloud" section, Trends Online contents now include records on:
The following presents the new and updated information included in Trends Online.
Historical Isotopic Temperature Record from the Vostok Ice Core (J.R. Petit et.al.) (http://cdiac.esd.ornl.gov/trends/temp/vostok/jouz_tem.htm)
Because isotopic fractions of oxygen-18 (18O) and deuterium (D) in snowfall are temperature-dependent and a strong spatial correlation exists between the annual mean temperature and the mean isotopic ratio (18O or dD) of precipitation, it is possible to derive ice-core climate records from the isotopic composition. This record was based on the 3623-m ice core drilled at the Vostok station in central east Antarctica, the deepest ice core ever recovered. The resulting core allowed the ice core record of climate properties at Vostok to be extended to 420,000 years BP.
From the extended Vostok record, Petit et al. concluded that present-day atmospheric burdens of carbon dioxide and methane seem to have been unprecedented during the past 420,000 years. Although the third and fourth climate cycles evident in the Vostok record are of shorter duration than the first two cycles, all four climate cycles show a similar sequence of a warm interglacial, followed by colder glacial events, and ending with a rapid return to an interglacial period. Minimum temperatures are within 1°C for the four climate cycles. The overall amplitude of the glacial-interglacial temperature change is ~8°C for the temperature above the inversion level and ~12°C for surface temperatures.
Global, hemispheric, and zonal temperature deviations derived from radiosonde records (J. K. Angell) (http://cdiac.esd.ornl.gov/trends/temp/angell/angell.html)
Data from a global network of 63 radiosonde stations were used to estimate global, hemispheric, and zonal annual and seasonal temperature deviations from 1958 through 1998. These estimates are categorized vertically (for the surface, troposphere, tropopause, low stratosphere, and the surface up to 100 mb) and horizontally (for the globe, the Northern and Southern Hemispheres, and the North and South Polar, North and South Temperate, North and South Subtropical, Tropical, and Equatorial latitudinal zones).
The data were obtained from values published in Monthly Climatic Data for the World and Climatic Data for the World, from the Global Telecommunications System (GTS) Network, and from National Center for Atmospheric Research files. Based on this network, Angell reported that during 1958-1998 the global, near-surface air temperature warmed by 0.14C/decade and the troposphere layer warmed by 0.10C/decade. The tropopause cooled in the extra tropics but warmed slightly in the tropics. The low-stratospheric layer cooled by about 0.4C/decade in the tropics and extra tropics. At both the surface and in the troposphere, 1998 was the warmest year of the 41-year record, but when the influence of the powerful El Niño of 1997-1998 on these temperatures is taken into account, 1990 remains the warmest year of the record.
These data are also available in NDP-008.
Trends in Total Cloud Amount Over China (Dale P. Kaiser) (http://cdiac.esd.ornl.gov/trends/clouds/kaiser/kaiser98.html)
A new section on clouds has been added to Trends Online. The first dataset offered in this new section was contributed by CDIAC's Dale Kaiser. The cloud data were extracted from a database of 6-hourly weather observations, covering 196 stations from 1951 through 1994, and provided by the National Climate Center of the China Meteorological Administration to CDIAC through a bilateral research agreement.
Station and regional trends in annual and seasonal mean cloud amount clearly indicate decreasing total cloud amount over much of China during this period. Most stations in central, eastern, and northeastern China show statistically significant decreases of 1 to 3% sky cover per decade. The decreasing trends in cloud amount over some China regions are especially interesting in light of recent temperature trends observed over China, which have shown significant increasing trends in daily minimum temperatures since 1951. The largest increases in minimum temperature have been observed in the northeastern part of the country, precisely where the strongest decreasing trends in total cloud amount are observed. In China, it seems that some different mechanism(s) must be considered for under-standing the observed increase in minimum temperatures, perhaps relating to atmospheric circulation or urbanization effects not fully removed from the temperature record.
Kyoto-Related Fossil-Fuel CO2 Emission Totals (Gregg Marland et.al.) (http://cdiac.esd.ornl.gov/trends/emis/annex.htm)
Included in the carbon dioxide emissions section, this table shows emissions of CO2 from fossil-fuel combustion and cement production in a format that is relevant for analyses relating to the Kyoto Protocol. The table lists emissions for those countries listed in Annex B of the Kyoto Protocol and for those countries not listed in Annex B (as well as providing lists of the countries in each category).
Atmospheric CO2 records from NOAA/CMDL (Kirk Thoning et.al.) (http://cdiac.esd.ornl.gov/trends/co2/nocm.htm)
The atmospheric carbon dioxide records from four sites in the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) continuous monitoring network have been updated to include data through 1998. Based on this continuous CO2 record, since 1974 the annual average atmospheric CO2 concentration at Point Barrow, Alaska, has risen from 333.94 parts per million by volume (ppmv) to 367.41 ppmv in 1998; at Mauna Loa, Hawaii, from 332.04 in 1976 to 366.49 ppmv in 1998; at Cape Matatula, American Samoa, from 331.45 in 1976 to 360.92 ppmv in 1996; and at the South Pole Observatory, from 329.33 in 1975 to 363.61 ppmv in 1998.
These observations are considered representative of "clean" concentrations in the well-mixed troposphere, free from confounding influences such as from vegetation or urban and industrial pollution; they quantify the increasing atmospheric concentrations of this most important greenhouse gas resulting from fossil-fuel combustion, land-use change, and cement production.
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