[Alexanderson and Moberg 1997]
Standard Normal Homogeneity Test applied to single shifts and gradual changes in time series.
Homogeneity test, temperature, SNHT.
[Basnett and Parker 1997]
Development of global 5 x 10 lat x lon historical slp data set. 1873-1994. Quality control and interpolation included.
Slp, quality control, interpolation.
[Beltrami et al. 1997]
Simultaneous inversion of borehole temperature profiles.
Slp, quality control, interpolation.
[Bryson 1997]
Interesting definition of climatology. ABSTRACT: An essay is, by definition, an initial, tentative ef-fort, or, alternately, an analysis or weighing from a personal point of view. The thoughts expressed in this essay are just that. They began as a personal attempt to arrive at a coherent theoretical basis for climatol-ogy. After much analysis and weighing of the facts, my conclusion was that the major problem lay with the definition of climate itself. The definition that I now use, which has the character of an axiom, leads to a number of corollaries. These in turn provide a rudimentary theoretical framework, or paradigm, for climatology as a distinctive atmospheric science. Climatology, the study of climate, is clearly a sci-ence, or at least a topic for scientific study, as attested by the fact that it is so often referred to in curricula, in scientific journals, and in the names of journals. How it relates to other sciences is less clear, for the definitions that can be found do not all agree, nor are they often supported either by reasoning or by tradi-tion. The first part of this essay deals with how I view the general position of climatology within the constel-lation of sciences. I then look at how the study of cli-mate differs from related fields.
Climatology
[Charles et al. 1997]
The oxygen isotopic composition of a banded coral from the western equatorial Indian Ocean provides a 150-year-long history of the relation between the El NinÜ o Southern Oscillation (ENSO) phenomenon and the Asian monsoon. Interannual cycles in the coral time series were found to correlate with Pacific coral and instrumental climate records, suggesting a consistent linkage across ocean basins, despite the changing frequency and amplitude of the ENSO. However, decadal variability that is characteristic of the monsoon system also dominates the coral record, which implies important interactions between tropical and midlatitude climate variability. One prominent manifestation of this interaction is the strong amplitude modulation of the quasi-biennial cycle.
Paleoclimate reconstruction, coral
[Cubasch et al. 1997]
Forced AOGCM ECHAM3-LSG with Hoyt and Sschatten solar index. T21 resolution. Delayed response mainly over the ocean. Dominant response is Glissberg cycle. Increased land-sea contrast.
ECHAM, solar forcing, global warming, little ice age, GCM
[Gosnold et al. 1997]
Abstract Ground-surface temperature (GST) histories, determined from a carefully selected set of twenty-nine borehole tempera- ture profiles, show a warming trend over the last century that increases systematically with latitude in the mid-continent of North America. Excepit one site in north Texas, the borehole locations lie within a 500 X 1000 km transect that extends from the Kansas-Nebraska border into southern Manitoba. Ground-surface warming during the last century increases from +0.4 C at 41.1 N to -t 2.O C at 49.6 N. Surface air temperature (SAT) warming in the transect, determined from Historical Climatology Network stations, increases from + 0S C per century at 40 N to + 1.6 C per century at 48.8 N. These warming trends agree with the regional warming pattern predicted by GCM simulations of global warming. However, the magnitudes of warming determined from the GST and the SAT data agree in regions where seasonal ground freezing does not occur but differ significantly where seasonal ground freezing does occur. Analysis of ground and air temperature coupling suggests that the greater warnnng observed in the GST histories in seasonally frozen ground is due to a secular increase in soil moisture that corresponds with increased precipitation during the past 50 years.
Paleoclimate reconstructions, borehole temperatures
[Griffies and Bryan 1997]
Attempt quantification of the NA and high latitude multidecadal variability. In order to assess the sensitivity of the model's multidecadal variability to the initial atmospheric state they made 4 ensembles each of them consisting of a number of members (8 or 12). For each ensemble the same ocean initial state is used and different atmospheric states. Theu use the GFDL model. Most of the variabililty in a 10000yr simulation comes form the THC in the North Atlantic and in the Greenland sea region. The first ensemble is associated to overturning and changes in seea surface properties. The second one is associated to southward propagation of freshwater anomalies from the East Greenland current to the North Atlantic. Both signals influence SST east of central Greenland. The third and forth ensembles are associated to extreme cases of the THC and bear more predictability. The basis of long term predictions relies on three characteristics: a) the ocean integrates the noisy atmospheric fluxes, b) the oscillatory type behavior of the THC, c) sst anomalies in northern north Atlantic which have an impact in European climate.
THC, predictability, North Atlantic.
[Hasselman 1997]
Discurse of the lines in climate change research after Kyoto
Climate change, global warming
[Huijzer and Isarin 1997]
Recomend use of many proxies for reconstruction.
Reconstructions, transfer functions, polen, biological and non biological proxies.
[Hurrell and van Loon 1997]
Hemispherical SLP, temperature and precipitation and heat fluxes. Regional trends linked to
changes in large scale circulation regimes. Pattern of temperature change related to NAO.
Interesting signal to noise ratio and calculation of eddi fluxes.
NAO, trends, temperature, precipitation, ...
[Jones et al. 1997]
Details of reconstruction with early instrumental data form Gibraltar and Reykjavik. Since early 1970s the most positive values have happened. 1995-96 most dramatic change in the index.
Nao, early instrumental reconstructions.
[Kerr 1997a]
The decadal oscillations in atmosphere can mask the climate change signal. NAO variability can explain most of the trends. Are these trends in circulation independent of the GHG warming?.
Nao, decadal variability.
[Kerr 1997b]
About ocean-atmosphere connection in the North Atlantic. Warm (cold) sst anomalies connected with sequence of NAO phases. The large memory of the ocean keeping sst anomalies can provide a source for decadal variability. The sst anomalies moving along the subpolar gyre can provide the energy for the NAO on decadal timescales and switching form one phase to another. A possible explanation for the temparature swithc in the ocean could be the Deep Western Boundary Current which travels southwards along the deep edge of N America. The DWBC could be cought up strengthening the Gulf Stream or can continue southward. This has implications for predictability of the atmospheric behavior.
Nao, decadal variability, ocean, DWBC, thermohaline circulation.
[Krinner et al. 1997]
Abstract: A high resolution GCM is used to examine the effect of changes in local surface climate parameters on the ice sheets that can influence the interpretation of the isotopic signal of the ice from deep cores. The model suggests that the 10C difference between the LGM surface temperature deduced from borehole thermometry and that deduced from the water isotope analysis to a great extent may be due to a modification of the precipitation seasonality in central Greenland. For central East Antarctica, the model tends to suggest a weak opposite bias.
Ice cores, boreholes, gcm
[Lau 1997]
A revision and discussion on the atmosphere ocean interaction to produce extratropical atmospheric variability.
Atmosphere, ocean, gcms.
[McCartney 1997]
Comments to [Sutton and Allen 1997]. Pose the question of wheather the ocean is just responding to the atmosphere or participates actively in decadal variability of regional climate. SST distributions of the link between atmosphere and ocean. Cold and windy mid to high latitude winter atmosphere causes convective overturning of the water column. The surface layer is heated in summer but the water mass characteristics persist below and so anomalies can persist for years with possible feedback to the atmosphere. It is possible that decadal variability in NAO is forced by coupling of atmosphere and ocean. Anomalies in Gulf Stream propagate slowly than the current due to meandering and spreading. Tropical and subtropical N Atlantic could be linked with implications for predictability.
Nao,Gulf stream, sst anomalies, decadal variability.
[Marshall et al. 1997]
Brief on the NAO topic. Coupled and uncoupled variability. Policies for improving understanding. Tropical variability.
Nao, tropical atlantic variability.
[Mart&́#305;n et al. 1997]
The quasigeostrophic theory used to address the role of diabatic forcing in synoptic scale processes over Iberia. Obtain parameterization of diabatic heating in terms the ice-liquid water potential temperature.
Ice-liquid water potential temperature. Iberian Peninsula. Quasigeostrophic theory.
[Overpeck et al. 1997]
Abstract:A compilation of paleoclimate records from lake sediments, trees, glaciers, and marine sediments provides a view of circum-Arctic environmental variability over the last 400 years. From 1840 to the mid-20th century, the Arctic warmed to the highest temperatures in four centuries. This warming ended the Little Ice Age in the Arctic and has caused retreats of glaciers, melting of permafrost and sea ice, and alteration of terrestrial and lake ecosystems. Although warming, particularly after 1920, was likely caused by in-creases in atmospheric trace gases, the initiation of the warming in the mid-19th century suggests that increased solar irradiance, decreased volcanic activity, and feedbacks internal to the climate system played roles.
Arctic, millennium, paleoclimate reconstructions, proxy records
[Rahmstorf 1997]
Ocean circulation stability depends nbot only on the total amount of GHG emitted by human activities but also on the rate at which gases are pumped to the atmosphere. Ocean circualtion warms the NA with ocean currents and THC. The rate of heat transport depends on small density differences and a subtle ballance of high latitudes cooling and freswater imputs. There is a threshold at which the THC can be shutted down with freshwater imput or warming. There is paleoclimatic evidence of this (Younger Dryas). GCM's show the THC is sensitive to GHG emissions. Intermediate complexity models show the same thing and that it is sensitive not only to the increse of GHG, but also to the rate of emmissions. The pfoblem is that GCMs have flux corrections which show artificial stability, convection in Greenland not well represented, etc. PP is also not well resolved. Speculation about consequences ... cooling or reduced warming over Greenland, possibility of drastic climate change, reduce of CO2 uptake by ocean...
Paleoclimate, THC, GHG, climate change.
[Safanda et al. 1997]
Abstract. The knowledge of the present-day underground temperatures may be important in the assessments of the past climate change. The method of inversion of the temperature-depth records into the ground surface temperature history is briefly introduced by showing an example of synthetic data and illustrated by a review of existing results obtained from the inversion of temperature logs measured in holes in the Czech Republic. Underground temperatures observed in holes of the depth of at least 1000 1500 m seem to confirm the preinstrumental climate pattern of the past several thousand years. Most of shallower temperature records (500 800 m) revealed general warming of climate followed the Little Ice Age of the 17 18th centuries and a pronounced increase of the soil temperatures by at least 1 K since the beginning of this century.
Paleoclimate reconstructions, borehole temperatures, Europe, Czech Republic
[Stephenson 1997]
Discusion of the Mahalanobis distance and its advantages and disadvantages in its use with climate variables.
Metric, Mahalanobis, SO
[Sutton and Allen 1997]
SST anomalies migration on decadal timescales over Gulf stream.Changes in
temperature off the coast of Florida evolve in agreement with pressure in Iceland and Azores. Influence on NAO. Similar mechanism to that of Latif and Barnet (1994) with a period of 6 years.
SST and Atmosphere. NAO. Great salinity anomaly.
[Valero et al. 1997]
Analysis of a heavy rain event in SW Iberia. Description of evolution of variables and indices.
Iberian Peninsula. Heavy rain events.
[Wilby and Wigley 1997]
Comparison of regression methods, weather pattern circulation-based approaches, stochastic weather generators and limited area models.
Statistical downscaling, regional models.
[Xie and Arkin 1997]
Gridded fields (analyses) of global monthly precipitation have been constructed on a 2.5° latitude longitude grid for the 17-yr period from 1979 to 1995 by merging several kinds of information sources with different characteristics, in-cluding gauge observations, estimates inferred from a variety of satellite observations, and the NCEP NCAR reanaly-sis. This new dataset, which the authors have named the CPC Merged Analysis of Precipitation (CMAP), contains pre-cipitation distributions with full global coverage and improved quality compared to the individual data sources. Exami-nations showed no discontinuity during the 17-yr period, despite the different data sources used for the different subperiods. Comparisons of the CMAP with the merged analysis of Huffman et al. revealed remarkable agreements over the global land areas and over tropical and subtropical oceanic areas, with differences observed over extratropical oceanic areas. The 17-yr CMAP dataset is used to investigate the annual and interannual variability in large-scale precipitation. The mean distribution and the annual cycle in the 17-yr dataset exhibit reasonable agreement with existing long-term means except over the eastern tropical Pacific. The interannual variability associated with the El Niño Southern Oscillation phenomenon resembles that found in previous studies, but with substantial additional details, particularly over the oceans. With complete global coverage, extended period and improved quality, the 17-yr dataset of the CMAP provides very useful information for climate analysis, numerical model validation, hydrological research, and many other applications. Further work is under way to improve the quality, extend the temporal coverage, and to refine the resolution of the merged analysis.
Global precipitation data set
[Zhang et al. 1997]
Precipitation in Portugal (daily) and SLP. Classification of circulation
patterns and relationship to precipitation. Downscaling Assessment of
changes and trends. Find upward trend in the NAO and downward trend
in the western circulation pattern. Decrease of spring rainfall.
Precipitation, Portugal, NAO, trends.
