File Name: difference between global warming and climate change .zip
On the other hand, the PDF change with global warming in different precipitation climatological zones presents another image. The reduced MP in richer precipitation zones resides in the PDF peak intensities, which linearly increase with the precipitation climatology zones. The global mean atmospheric hydrological cycle is projected to intensify with the global warming due to the increased anthropogenic greenhouse gas emission.
Global mean precipitation has been found to increase in both observations Gu et al. For example, Wentz et al. Adler et al. Patterns of precipitation and storm events are likely to change as well since precipitation is directly impacted by changes of atmospheric circulation in addition to the increases in water vapour with a warmer climate. Chou and Neelin, ; Held and Soden, ; Boucher et al. In this mechanism, the increased water vapour gives rise to the positive negative precipitation anomalies over climatological wet dry regions, provided that circulation is unchanged, only carrying more moisture around.
In particular, the amount of precipitation is not only controlled by the intensity but also by the frequency. A number of model studies suggest that there is more intensive precipitation but less precipitation frequency resulting from global warming Wilby and Wigley, The discrepancy between heavy precipitation and mean precipitation changes implies that precipitation frequency should decrease in order to offset the large increase in extreme precipitation Trenberth et al. Later, observations and model simulations obtained consistent results that extreme precipitation tends to become more frequent in most regions Groisman et al.
However, the increasing rate of precipitation extremes simulated with climate models does not match the rate of water vapour content changes O'Gorman and Schneider, ; Lu et al. Although changes in precipitation characteristics have been investigated by many previous studies, conclusions remain substantially diverse on the precipitation changes at regional scale even for relatively large spatial averages Allan and Soden, ; ; Chou et al.
The preceding analyses usually simply divided precipitation into light, moderate and heavy categories using very limited intervals. This study, however, utilizes dense intensity intervals to systematically examine the probability distribution function PDF of changes in both frequency and amount. The regional variations of precipitation characteristic changes are discussed by categorizing the areas into different latitudes and different precipitation climatological zones.
Project Athena is an international collaboration involving five institutions, in response to the call for a revolution in seamless weather and climate modelling made at the World Modelling Summit, held in May in Reading, United Kingdom Shukla et al. Kinter et al. The spectral transform method is used for the computation of advection, the physical parametrizations, as well as the nonlinear terms so that they can be conducted on the linear reduced Gaussian grid Hortal and Simmons, IFS is discretized with 91 hybrid vertical levels top full level at 0.
The coupling between the dynamics and physics and the individual parametrization schemes is given by Beljaars et al. The convection parametrization is based on a mass flux scheme described in Tiedtke Details of the original prognostic cloud scheme are given in Tiedtke The radiation package is described in Morcrette et al. Most of the parametrization schemes were left unchanged across all resolutions. For the convection scheme, however, the convective adjustment time is resolution dependent, and is longer in relatively lower resolutions i.
The detailed observation sources and all types of experiments are described in Jung et al. These data are monthly before and weekly starting from , and are then interpolated to daily values and spatially to the grid of the model.
With the IFS and covering the period —, this experiment was also carried out at T and T Both SST and sea ice changes were taken as the difference between — and — monthly climatologies from the Community Climate System Model CCSM simulation with the assumption of the atmospheric greenhouse gas and aerosol concentrations following the Intergovernmental Panel on Climate Change IPCC emissions scenario A1B until the year , thereafter being constant at their values Collins et al.
Monthly values were then linearly interpolated to daily values. The atmospheric greenhouse gases of this experiment also follow the A1B scenario Nakicenovic et al. Only simulations at T resolution for both AMIP and TS experiments are analysed because its resolution is similar to that of the observed dataset chosen for comparison.
The difference between TS and AMIP runs will be referred to as the response to climate warming in the context of this study. This dataset has a horizontal resolution of 0. We adopt the 3B42 precipitation data from to in this study. The meridional structure of the changes is in general consistent with previous simulations Sun et al. Chou et al. Measuring changes in precipitation frequency and intensity is also crucial to assessing the impacts of global warming Trenberth et al.
For a given latitude, the PDF is obtained by assembling all daily precipitation data of that latitude, and computing the histogram based on these data.
This histogram is then normalized by the number of years. The binning for the histogram calculation is set, according to the precipitation intensity, into three segments including 90 elements in total. The first segment has five bins: 0—0.
The design of the sampling bins allows us to construct smooth PDFs spectra in different latitudes, thus it is applied to all latitudes. They both have the general tendency of decreasing frequency with the intensity at all latitudes. The major centre resides at the Tropics corresponding to the intertropical convergence zone ITCZ , and the other two at the midlatitudes corresponding to the storm tracks of both hemispheres.
Dai, The PDF of frequency in each intensity bin is the average number of days per year when the precipitation rate falls within the bin. In each latitude, the summation of frequency PDF across precipitation intensity spectrum in a and b is days [Colour figure can be viewed at wileyonlinelibrary.
These two panels show consistent patterns by definition. The most remarkable feature is the increase in HP frequency over all latitudes, which has been noticed by several observational and modelling studies Houghton et al.
It suggests that heavy precipitation will happen more frequently in the future under a warmer scenario. In addition, compared to other regions in the low latitudes, the narrow equatorial belt stands out with a significant decrease of LP and increase in HP. Similarly, the PDF of precipitation accumulation sums up the annual accumulation of precipitation for each intensity bin. In each latitude, the summation of frequency PDF across precipitation intensity spectrum in a and b is days, and the summation of the PDF accumulation across precipitation intensity spectrum in d and e is the total annual mean precipitation amount, respectively [Colour figure can be viewed at wileyonlinelibrary.
Overall, in the Tropics and subtropics wherever there is a decrease of LP, there is an increase of MP and HP, indicating that total increase of precipitation occurs as the result of a spectral shift from weak events to intensive events, and vice versa for the decrease of total precipitation.
The most notable is the intensification in the eastern equatorial Pacific sandwiched by the surrounding reduction in the changes of MP and HP. There is an intriguing exception over tropical Africa, where all three categories increase. After inspecting the PDF distribution of the background accumulative precipitation, this appears to be attributable to the poleward shift of the PDF spectrum near the midlatitudes.
It is clear that this asymmetry can be attributed to the difference of surface conditions. Climate change has altered not only the overall magnitude of rainfall but also its seasonal distribution Easterling et al. In the Tropics and subtropics, precipitation change pattern is more regional. The decline in Southern Africa and the dry Brazilian region is more significant in austral winter than austral summer.
This large precipitation decrease in Southern Africa has been documented in Solomon et al. Each belt, in terms of the AMIP simulated precipitation climatology, is in turn categorized into 16 precipitation climatological zones using the precipitation rate intervals: 0.
A precipitation climatological zone, denoted as R clim , is defined according to the precipitation interval that the regional climatological precipitation falls in. In addition, the extreme precipitation in both panels increases with the climate zone. Meantime, the biases of AMIP spectral pattern are also readily discernible. The overestimate of LP is a common caveat of climate models, which tend to drizzle too much. As the consequence, since the total precipitation is constrained by the radiative properties of the atmosphere, and hence cannot deviate too much from reality, the simulated HP has to compensate for the overestimate of the LP.
This might represent a major deficiency of the IFS model in capturing the subtropical precipitation distribution. The frequency PDF contours from a are superimposed in c. The thick black line in c shows the occurrence fractional distribution with R clim s i.
The red line in the lower part of c shows fractional occurrence changes i. The thick black line in f represents the fractional precipitation amount distribution with R clim s i. The upward tilt of Centre 1 is, therefore, an indication that the precipitation intensities where the PDF peak lies increase with the rank of precipitation climate zones. Actually, the intensities of the PDF peaks roughly linearly increase with the precipitation climatology when we plot the figure with equal intervals for both axes not shown.
Otherwise said, regions with richer precipitation have heavier main precipitation systems. On the other hand, the modal value of Centre 2 does not vary much with the rank of the climate zones, implying a weak precipitation circulation regime of the atmosphere irrespective of the geographic locations.
The corresponding precipitation frequency PDFs and the fractional distributions with precipitation climatological regions from AMIP, in both a and c , are also respectively superimposed by contours and thick black lines [Colour figure can be viewed at wileyonlinelibrary. The frequency PDFs in different climatological regions from AMIP are also overlaid on the corresponding panels by contours [Colour figure can be viewed at wileyonlinelibrary.
In very dry zones with climatological precipitation rate less than 0. The fractional distributions of precipitation climatology in different zones thick black lines show broader spread in all four panels, indicating the Tropics have diverse climatological precipitation from very dry precipitation to very wet precipitation. In addition, the HP increase is larger over tropical land than tropical ocean in all climatological zones.
The difference between them lies in the relative magnitude of changes. The increases of HP are stronger than LP in the frequency spectrum change, while this is reversed in the accumulation spectrum change. In extratropical regions, precipitation has strong seasonal dependence. Thus, the PDF differences of daily precipitation accumulation in different climatological zones are examined separately for summer and winter seasons. The PDFs are constructed by grouping the data from both hemispheres for a given season, i.
For brevity, only accumulation PDF and the related changes are presented for the extratropical regions. The major differences between subtropical winter and summer precipitation accumulation PDF changes lie in the LP. Compared to the Tropics and subtropics, the mid—high latitudes have less precipitation and a narrower range of the main precipitation climatology zones. Two PDF spectrum centres appear in all seasons and over both land and ocean for all three latitudinal belts.
The spectrum centre in higher precipitation climate zones becomes less apparent in a higher latitudinal belt. Both include the components of HP increases and MP decreases. However, the LP changes can be dependent on seasons and underlying surfaces. The revelation of more frequent heavy precipitation is consistent with previous studies Trenberth et al.
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Said another way, global warming is one symptom of the much larger problem of human-caused climate change. Global warming is just one symptom of the much larger problem of climate change. NOAA Climate. Another distinction between global warming and climate change is that when scientists or public leaders talk about global warming these days, they almost always mean human -caused warming—warming due to the rapid increase in carbon dioxide and other greenhouse gases from people burning coal, oil, and gas. Climate change, on the other hand, can mean human-caused changes or natural ones, such as ice ages.
Climate change is a threat to the future of our planet, but there is still time for us to adapt to it and mitigate its effects. Below, we take a look at the measures being put in place and travel in time to see what the world will look like if we are to halt global warming. Policies on adapting to climate change will help us withstand the consequences of global warming. Global temperature records are being continually broken. If last July was the hottest month in history, according to the World Meteorological Organisation WMO , the five-year period is about to become the hottest of all time.
Global warming refers only to the Earth's rising surface temperature, while climate change includes warming and the “side effects” of.
Similarly, the terms "weather" and "climate" are sometimes confused, though they refer to events with broadly different spatial- and timescales. Weather refers to atmospheric conditions that occur locally over short periods of time—from minutes to hours or days. Familiar examples include rain, snow, clouds, winds, floods or thunderstorms.
Global Warming - Impacts and Future Perspective. Global warming and climate change refer to an increase in average global temperatures. Natural events and human activities are believed to be main contributors to such increases in average global temperatures.
On the other hand, the PDF change with global warming in different precipitation climatological zones presents another image.Reply