IPCC Climate Change Data: NIES99 A1a Model: 2050 Maximum Temperature

The model used here is a coupled ocean-atmosphere model that
consists of the CCSR/NIES atmospheric GCM, the CCSR ocean GCM, a
thermodynamic sea-ice model, and a river routing model
(Abe-Ouchi et al., 1996). The spatial resolution is T21 spectral
truncation (roughly 5.6 degrees latitude/longitude) and 20
vertical levels for the atmospheric part, and roughly 2.8
degrees horizontal grid and 17 vertical levels for the oceanic
part. Flux adjustment for atmosphere-ocean heat and water
exchange is applied to prevent a drift of the modelled climate.
The atmospheric model adopts a radiation scheme based on the
k-distribution, two-stream discrete ordinate method (DOM)
(Nakajima and Tanaka, 1986). This scheme can deal with
absorption, emission and scattering by gases, clouds and aerosol
particles in a consistent manner. In the calculation of sulphate
aerosol optical properties, the volumetric mode radius of the
sulphate particle in dry environment is assumed to be 0.2
micron. The hygroscopic growth of the sulphate is considered by
an empirical fit of d'Almeida et al. (1991). The vertical
distribution of the sulphate aerosol is assumed to be constant
in the lowest 2 km of the atmosphere. The concentrations of
greenhouse gases are represented by equivalent-CO2. Three
integrations are made for 200 model years (1890-2090). In the
control experiment (CTL), the globally uniform concentration of
greenhouse gases is kept constant at 345 ppmv CO2-equivalent and
the concentration of sulphate is set to zero. In the experiment
GG, the concentration of greenhouse gases is gradually
increased, while that of sulphate is set to zero. In the
experiments GS, the increase in anthropogenic sulphate as well
as that in greenhouse gases is given and the aerosol scattering
(the direct effect of aerosol) is explicitly represented in the
way described above. The indirect effect of aerosol is not
included in any experiment. The scenario of atmospheric
concentrations of greenhouse gases and sulphate aerosols is
given in accordance with Mitchell and Johns (1997). The increase
in greenhouse gases is based on the historical record from 1890
to 1990 and is increased by 1 percent / yr (compound) after
1990. For sulphate aerosols, geographical distributions of
sulphate loading for 1986 and 2050, which are estimated by a
sulphur cycle model (Langer and Rodhe, 1991), are used as basic
patterns. Based on global and annual mean sulphur emission
rates, the 1986 pattern is scaled for years before 1990; the
2050 pattern is scaled for years after 2050; and the pattern is
interpolated from the two basic ones for intermediate years to
give the time series of the distribution. The sulphur emission
rate in the future is based on the IPCC IS92a scenario. The
sulphate concentration is offset in our run so that it starts
from zero at 1890. The seasonal variation of sulphate
concentration is ignored. Discussion on the results of the
experiments will be found in Emori et al. (1999). Climate
sensitivity of the CCSR/NIES model derived by equilibrium runs
is estimated to be 3.5 degrees Celsius. Global-Mean Temperature,
Precipitation and CO2 Changes (w.r.t. 1961-90) for the CCSR/NIES model. From the IPCC website: The A1 Family storyline is a case of
rapid and successful economic development, in which regional
averages of income per capita converge - current distinctions
between poor and rich countries eventually dissolve. In this
scenario family, demographic and economic trends are closely
linked, as affluence is correlated with long life and small
families (low mortality and low fertility). Global population
grows to some nine billion by 2050 and declines to about seven
billion by 2100. Average age increases, with the needs of
retired people met mainly through their accumulated savings in
private pension systems. The global economy expands at an
average annual rate of about three percent to 2100. This is
approximately the same as average global growth since 1850,
although the conditions that lead to a global economic in
productivity and per capita incomes are unparalleled in history.
Income per capita reaches about US$21,000 by 2050. While the
high average level of income per capita contributes to a great
improvement in the overall health and social conditions of the
majority of people, this world is not without its problems. In
particular, many communities could face some of the problems of
social exclusion encountered by the wealthiest countries in the
20th century and in many places income growth could come with
increased pressure on the global commons. Energy and mineral
resources are abundant in this scenario family because of rapid
technical progress, which both reduce the resources need to
produce a given level of output and increases the economically
recoverable reserves. Final energy intensity (energy use per
unit of GDP) decreases at an average annual rate of 1.3 percent.
With the rapid increase in income, dietary patterns shift
initially significantly towards increased consumption of meat
and dairy products, but may decrease subsequently with
increasing emphasis on health of an aging society. High incomes
also translate into high car ownership, sprawling
suburbanization and dense transport networks, nationally and
internationally. Land prices increase faster than income per
capita. These factors along with high wages result in a
considerable intensification of agriculture. Three scenario
groups are considered in A1 scenario family reflecting the
uncertainty in development of energy sources and conversion
technologies in this rapidly changing world. Near-term
investment decisions may introduce long-term irreversibilities
into the market, with lock-in to one technological configuration
or another. The A1B scenario group is based on a balanced mix of
energy sources and has an intermediate level of CO2 emissions,
but depending on the energy sources developed, emissions in the
variants cover a very wide range. In the fossil-fuel intensive
scenario group A1FI, emissions approach those of the A2
scenarios; conversely in scenario group A1T with low labor
productivity or of rapid progress in "post-fossil"
energy technologies, emissions are intermediate between those of
B1 and B2. These scenario variants have been introduced into
the A1 storyline because of its "high growth with high
tech" nature, where differences in alternative technology
developments translate into large differences in future GHG
emission levels Ecological resilience is assumed to be high in
this storyline. Environmental amenities are viewed in a
utilitarian way, based on their influence on the formal economy.
The concept of environmental quality might change in thisstoryline from"conservation" of nature to active
"management" - and marketing - of natural and
environmental services. Data are available for the following
periods: 1961-1990, 2010-2039; 2040-2069; and 2090-2099 Mean
monthly and change fields.