Adjacent Coastal Region Research Articles

Annual intensification of the Somali jet in a quasi‐equilibrium framework: Observational composites

AbstractThe annual intensification of the Somali jet, which accompanies the onset of the Indian summer monsoon, is rapid compared to the evolution of the seasonal insolation forcing. Using observationally‐based data sets, the dynamic and thermodynamic changes accompanying the onset of this jet are presented. The abrupt component of jet onset is shown to occur over ocean about 1000km east of the East African highlands, and is accompanied by increases in both deep convection and baroclinic flow over the off‐equatorial Arabian Sea. These abrupt changes are well separated from the core of the cross‐equatorial jet, which is located over land adjacent to the East African highlands.The onset of the Somali jet and the associated monsoon are then examined in a convective quasi‐equilibrium framework. Such a framework is consistent with the mean summer state, in that peak free‐tropospheric temperatures are nearly collocated with peak subcloud layer entropies over the northern Bay of Bengal and adjacent coastal regions. Jet onset is accompanied by a large ($\hbox{O}\{100\ \hbox{W m}^{-2}\}$) increase in surface enthalpy flux over the Arabian Sea that is nearly collocated with, and linearly related to, the concurrent increase in deep tropospheric ascent. At the same time, the highest subcloud entropies shift inland slightly from the Bay of Bengal, and the region of warmest free‐tropospheric temperatures expands poleward. The consistency of all of these changes with a wind—evaporation feedback and several other hypothesized mechanisms of abrupt monsoon onset is discussed. Copyright © 2009 Royal Meteorological Society

Projected Changes in Eurasian and Arctic Summer Cyclones under Global Warming in the Bergen Climate Model

Using the coupled ocean-atmosphere Bergen Climate Model, and a Lagrangian vorticity-based cyclone tracking method, the authors investigate current climate summer cyclones in the Northern Hemisphere and their change by the end of the 21st century, with a focus on Northern Eurasia and the Arctic. The two scenarios A1B and A2 for increasing greenhouse gas concentrations are considered. In the model projections, the total number of cyclones in the Northern Hemisphere is reduced by about 3%–4%, but the Arctic Ocean and adjacent coastal regions harbour slightly more and slightly stronger summer storms, compared to the model current climate. This increase occurs in conjunction with an increase in the high-latitude zonal winds and in the meridional temperature gradient between the warming land and the ocean across Northern Eurasia. Deficiencies in climate model representations of the summer storm tracks at high latitudes are also outlined, and the need for further model inter-comparison studies is emphasized.

Bioavailability of macroalgal dissolved organic matter in seawater

The bioavailability of macroalgal dissolved organic matter (DOM) was examined by decomposition experiments using released DOM from Ecklonia cava Kjellman (Phaeophyceae) living in Oura Bay, Shimoda, Izu Peninsula, Japan. The samples used for the decomposition experiments were obtained by enclosing the plants in bags. Based on the reduction rates of the concentrations of dissolved organic carbon (DOC), the turnover times of the macroalgal DOC were calculated to be between 24 and 172 d, with monthly-seasonal timescales. These values were mostly higher than those of phytoplanktonic DOC in previous studies (<1 mo). The relatively longer turnover time probably reflects the bio-refractory property of the macroalgal DOM. In most of the experiments (except for June), fucans and humic-like material were the major constituents of the released DOM. The fucans appeared to be partly decomposed during the experiments, but the compositional changes in the neutral carbohydrates in these seasons were less definite than those in June. The fluorescent intensity of the humic-like material did not decrease with time, suggesting a refractory character. Macroalgae are likely important DOM producers in Oura Bay, because the daily DOM production of E. cava accounts for 1.5 to 34% of DOM stock in Oura Bay per day. The concentration and the distribution of DOC inside and outside the bay strongly sug- gests that the released DOM was extensively exported out of the bay. These facts indicate that the macroalgal DOM contributes to marine DOM pools in a wider area including the adjacent coastal region.

Morphology and tectonics of Mahanadi Basin, northeastern continental margin of India from geophysical studies

The bathymetry, total intensity magnetic and satellite free-air gravity data over the eastern continental margin of India between the latitudes 18° 30′N and 20°N within the water depths of 25–2300 m (between Paradip and Gopalpur) were analyzed and interpreted. Onshore aeromagnetic and Bouguer gravity data over the adjacent coastal region are also supplemented in the present analysis. The basement configuration inferred from the bathymetry, magnetic and gravity data resembles a series of coast-parallel structural highs and depressions and their shearing pattern in the Mahanadi offshore Basin. The Chilika offshore lineament and Dhamara offshore lineament constitute the southern and northern boundaries of the offshore basin respectively. In this sector, the inferred Continent Ocean Boundary (COB), around 170 km from the coast, approximately mimics the 2000 m isobath. The width of the inferred offshore basin between the Chilika Offshore Lineament and Dhamara Offshore Lineament is around 240 km and it extends approximately up to 170 km from coast to offshore (perhaps up to the COB). The inferred tectonics of the northeastern continental margin of India suggests pull-apart and sheared/transform mechanisms during the breakup of India from Antarctica. The model studies suggest that the northern part of the 85°E Ridge abuts the coast at Chilika Lake. The shape of 2000 m isobath over the northeastern continental margin of India closely resembles to that of 2000 m isobath off the Lambert Graben of East Antarctica. This inference appears to further support the theory that the eastern continental margin of India and East Antarctica are closely aligned in the pre-breakup tectonic setting of the eastern Gondwanaland.

Effects of an estuarine plume-associated bloom on the carbonate system in the lower reaches of the Pearl River estuary and the coastal zone of the northern South China Sea

We observed a phytoplankton bloom downstream of a large estuarine plume induced by heavy precipitation during a cruise conducted in the Pearl River estuary and the northern South China Sea in May–June 2001. The plume delivered a significant amount of nutrients into the estuary and the adjacent coastal region, and enhanced stratification stimulating a phytoplankton bloom in the region near and offshore of Hong Kong. A several fold increase (0.2–1.8 μg Chl L −1) in biomass (Chl a) was observed during the bloom. During the bloom event, the surface water phytoplankton community structure significantly shifted from a pico-phytoplankton dominated community to one dominated by micro-phytoplankton (>20 μm). In addition to increased Chl a, we observed a significant drawdown of pCO 2, biological uptake of dissolved inorganic carbon (DIC) and an associated enhancement of dissolved oxygen and pH, demonstrating enhanced photosynthesis during the bloom. During the bloom, we estimated a net DIC drawdown of 100–150 μmol kg −1 and a TAlk increase of 0–50 μmol kg −1. The mean sea–air CO 2 flux at the peak of the bloom was estimated to be as high as ∼−18 mmol m −2 d −1. For an average surface water depth of 5 m, a very high apparent biological CO 2 consumption rate of 70–110 mmol m −2 d −1 was estimated. This value is 2–6 times higher than the estimated air–sea exchange rate.

A note on propagating rainfall episodes over the Bay of Bengal

AbstractAn observational analysis of precipitation episodes over the Bay of Bengal and the adjacent coastal region is conducted using the TRMM Real‐Time Multi‐Satellite Precipitation Analysis (MPA‐RT) products for three warm seasons (i.e. May to September for 2002–2004). Time–distance diagrams (Hovmüller diagrams) of rainfall episodes reveal frequent travelling precipitation episodes having lifetimes greatly exceeding those of individual convective systems. The majority of the episodes translate southward and many do not appear to have a steering level (i.e. they propagate in a hydraulic‐like manner), unlike those previously documented over midlatitude and tropical continents which usually have a steering level. On average, the coherent systems have a latitudinal span of 5 degrees and a 1‐day duration and a meridional propagation speed of 8 m s−1, approximately. The episodes mostly initiate over the coastal land around midday and offshore around midnight. Copyright © 2008 Royal Meteorological Society

Water quality responses to simulated flow and nutrient reductions in the Cape Fear River Estuary and adjacent coastal region, North Carolina

In order to examine system responses to high river discharge events and nutrient loading variations from the drainage basin, a coupled three-dimensional hydrodynamic and water quality model was applied in the Cape Fear River Estuary (CFRE) and its adjacent coastal region. An empirical equation was introduced in the model to represent light limitation for phytoplankton growth due to chromophoric dissolved organic matter (CDOM). Model results show that in the upper to middle estuary, light limitation controls phytoplankton growth while in the lower estuary phytoplankton growth appears to be limited by light intensity during high flow periods, but by nutrient availability during low flow periods. In the coastal ocean, nutrient availability is usually the dominant limiting factor for primary production. Two sensitivity model tests were conducted to predict the system response to reductions in nutrient loading from the drainage basin. By reducing river discharge, the model results show that phytoplankton growth was enhanced within CFRE due to alleviated light limitation and increased residence time. More nutrients were consumed within the CFRE, and less were exported to the coastal region. By reducing nutrient concentrations at the head of the estuary, chlorophyll a concentrations within the CFRE were decreased. Less nutrients were consumed within the CFRE, and only slightly less were exported to the coastal region. The supply of light limiting substances during high flow events acted against the effect of riverine nutrient enhancement on phytoplankton growth, creating a negative feedback mechanism.

Mixing of a dye tracer in the Delaware plume: Comparison of observations and simulations

In April 2003 we injected Rhodamine‐WT fluorescent dye into the halocline at the base of the Delaware River plume during an upwelling event. The dye immediately bifurcated: One third of the dye moved offshore with a portion of the plume, while the other 2/3 remained within the halocline, near the coastline. This behavior has not been previously observed, and it presents a strong challenge to contemporary coastal ocean models. Here we employ a numerical model of Delaware Bay and the adjacent coastal region that incorporates the Mellor‐Yamada Level 2.5 turbulence closure scheme to simulate the observed dye injection event. Comparison between the simulation and observations reveals that the model is able to successfully reproduce the flow field, simulating the separation and subsequent advection of the dye. Consequently, the simulation is used to examine the relative effects of wind‐ and buoyancy‐driven transport on mixing and advection of the dye. Comparison of simulated and observed plumes reveals that the model accurately reproduces the observed mixing and accompanying vertical salt flux within the offshore plume. Examination of the simulation reveals a unique combination of wind‐ and buoyancy‐driven flow that results in the dye remaining in the halocline of the onshore plume despite significant vertical mixing due to winds. The strong stratification within the inshore plume causes the closure scheme to shut off the vertical diffusivities, leaving the circulation model with arbitrarily chosen constant background values. Varying these values reveals only a weak dependence of the salt flux within the highly stratified regions due to the highly localized nature of the salt flux.

Oceanographic characteristics of Baía de Todos os Santos, Brazil

Based on a vast set of in situ data, a first comprehensive overview of the oceanographic characteristics of Baía de Todos os Santos (BTS) is provided. BTS is the second largest coastal bay in Brazil (maximum area of 1223 km² and average depth of 9.8 m), and is located in the northeast Brazil, in the vicinity of Salvador city. The circulation inside the bay is mostly tidally driven and does not vary significantly throughout the year. On the other hand, the wet (winter) and dry (summer) seasons does alter significantly the distribution of water properties inside the BTS. During summer, the waters inside the bay have oceanic characteristics, with Tropical Water (TW) penetrating along the whole region, except for the mouth of Rio Paraguaçu. The water temperature inside the bay is higher than in the coastal zone, and variations can be up to 3°C, reaching a maximum of nearly 30°C. During winter, with the increase of freshwater inflow, salinity variations of about 4 are observed between the innermost stations inside BTS and the adjacent coastal region. Salinity values inside the bay can be as low as 32.3, inhibiting the penetration of TW into the BTS, which is totally occupied by a locally formed Coastal Water (CW). An evaluation of the flushing time is also provided and shows that during summer, a 60-fold increase can be observed compared to winter (38 days). While the circulation does not vary seasonally inside the bay, the associated inner shelf is characterized by two different scenarios. During summer, the upwelling favorable easterlies drive a southwestward flow, while during winter the more frequent occurrence of cold fronts (southerly winds) tend to reverse the circulation.

Stable isotopes in juvenile marine fishes and their invertebrate prey from the Thames Estuary, UK, and adjacent coastal regions

Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes, potentially providing a thermal resource, refuge from predators and a source of abundant prey. Stable isotope analysis may be used to assess relative resource use from isotopically distinct sources. This study comprised two major components: (1) development of a spatial map and discriminant function model of stable isotope variation in selected invertebrate groups inhabiting the Thames Estuary and adjacent coastal regions; and (2) analysis of stable isotope signatures of juvenile bass ( Dicentrarchus labrax), sole ( Solea solea) and whiting ( Merlangius merlangus) for assessment of resource use and feeding strategies. The data were also used to consider anthropogenic enrichment of the estuary and potential energetic benefits of feeding in estuarine nursery habitat. Analysis of carbon (δ 13C), nitrogen (δ 15N) and sulphur (δ 34S) isotope data identified significant differences in the ‘baseline’ isotopic signatures between estuarine and coastal invertebrates, and discriminant function analysis allowed samples to be re-classified to estuarine and coastal regions with 98.8% accuracy. Using invertebrate signatures as source indicators, stable isotope data classified juvenile fishes to the region in which they fed. Feeding signals appear to reflect physiological (freshwater tolerance) and functional (mobility) differences between species. Juvenile sole were found to exist as two isotopically-discrete sub-populations, with no evidence of mixing between the two. An apparent energetic benefit of estuarine feeding was only found for sole.

The effect of wave–current interactions on the storm surge and inundation in Charleston Harbor during Hurricane Hugo 1989

The effects of wave–current interactions on the storm surge and inundation induced by Hurricane Hugo in and around the Charleston Harbor and its adjacent coastal regions are examined by using a three-dimensional (3-D) wave–current coupled modeling system. The 3-D storm surge and inundation modeling component of the coupled system is based on the Princeton ocean model (POM), whereas the wave modeling component is based on the third-generation wave model, simulating waves nearshore (SWAN). The results indicate that the effects of wave-induced surface, bottom, and radiation stresses can separately or in combination produce significant changes in storm surge and inundation. The effects of waves vary spatially. In some areas, the contribution of waves to peak storm surge during Hurricane Hugo reached as high as 0.76 m which led to substantial changes in the inundation and drying areas simulated by the storm surge model.

A numerical study on hurricane‐induced storm surge and inundation in Charleston Harbor, South Carolina

A storm surge and inundation model is configured in Charleston Harbor and its adjacent coastal region to study the harbor's response to hurricanes. The hydrodynamic component of the modeling system is based on the Princeton Ocean Model, and a scheme with multiple inundation speed options is imbedded in the model for the inundation calculation. Historic observations (Hurricane Hugo and its related storm surge and inundation) in the Charleston Harbor region indicate that among three possible inundation speeds in the model, taking Ct (gd)1/2 (Ct is a terrain‐related parameter) as the inundation speed is the best choice. Choosing a different inundation speed in the model has effects not only on inundation area but also on storm surge height. A nesting technique is necessary for the model system to capture the mesoscale feature of a hurricane and meanwhile to maintain a higher horizontal resolution in the harbor region, where details of the storm surge and inundation are required. Hurricane‐induced storm surge and inundation are very sensitive to storm tracks. Twelve hurricanes with different tracks are simulated to investigate how Charleston Harbor might respond to tracks that are parallel or perpendicular to the coastline or landfall at Charleston at different angles. Experiments show that large differences of storm surge and inundation may have occurred if Hurricane Hugo had approached Charleston Harbor with a slightly different angle. A hurricane's central pressure, radius of maximum wind, and translation speed have their own complicated effects on surge and inundation when the hurricane approaches the coast on different tracks. Systematic experiments are performed in order to illustrate how each of such factors, or a combination of them, may affect the storm surge height and inundation area in the Charleston Harbor region. Finally, suggestions are given on how this numerical model system may be used for hurricane‐induced storm surge and inundation forecasting.

Drought effects on pelagic properties in the shallow and turbid Patos Lagoon, Brazil

The effect of a 7-mo drought (La Nina 1988) was evaluated on pelagic properties in the large Patos Lagoon (30°12′–32°12′S, 50°40′–52°15′W). From December 1987 to December 1988, surface water was sampled along the longitudinal axis of the lagoon for temperature (10–29°C), salinity (0–31.4), dissolved inorganic phosphate (0.02–4.73 μM), nitrate (0.05–66.25 μM), nitrite (0.01–3.54 μM), ammonium (0.09–33.19 μM), silicate (1.11–359.20 μM), phytoplankton chlorophylla (chl; 0.4–41.2 mg m−3), primary production (gross PP 1.72–161.82 mg C m3 h−1; net PP 0.04–126.19 mg C m3 h−1), and species composition and abundance (42–4,961 ind ml−1). In the wet season the whole system acted as a river and light availability limited phytoplankton growth. During the drought from February to August monthly freshwater runoff was low and the inflow of marine water to the southern sector generated spatial variability of the analyzed properties and five functional areas were recognized. The northernmost Guaiba River (1) presented low light availability and phytoplankton chl concentration compared to the northern limnetic area (2) (chl mean 13.3 μg I−1; max 41.2 μg I−1; gross PP mean 52.6 mg C m3 h−1), which acted as a biological filter removing dissolved inorganic nutrients. Silicate concentration was strongly diminished in this area due to diatom uptake (Aulacoseira granulata, 9,330 cells ml−1). In the northern limnetic and central oligohaline (3) areas, phytoplankton biomass was controlled by light but nitrogen also played a limiting role. In the southern area (4) that is under marine influence, low chl concentration (mean 4.5 μg I−1) and gross PP (mean 28.1 mg C m3 h−1) coincided with co-limitation of nitrogen and light while the channel to the ocean (5) was strongly light limited. This study demonstrated that low light and high silicate input had a buffer effect at Patos Lagoon, hampering negative expression of cultural eutrophication. The main effect during the drought period occurred in the northern limnetic region, where low silicate values due to diatom uptake led to higher cyanobacteria abundance, and enhanced mineralization occurred in the central oligohaline lagoon. Increased rainfall resulted in light limitation and decreasing primary production in the entire freshwater lagoon, and the adjacent coastal region benefited from nutrient enrichment.

Land‐borders and sea‐borders: An exploration of differences in border region development

Land‐borders and the adjacent regions have attracted considerable attention since the early 1980s. However, there has been a neglect of sea‐borders and the adjacent coastal regions. This paper has the aim to signal differences in development between land‐border and sea‐border regions, based on a different historical development of interaction costs in cross‐border transport and on differences in the characteristics of land‐borders and sea‐borders. To this purpose, the focus is on two types of border impacts on border regions, i.e., interaction between adjacent border regions (mainly in transport) and economic development of these regions. Border impacts are illustrated with examples from a small country, the Netherlands, with an almost equal length of land‐borders and sea‐borders. The paper concludes with a summary and indications of future research.

Marine Bird Attraction to Thermal Fronts in the California Current System

AbstractI relate marine bird density to the 55 strongest thermal fronts encountered during a survey of much of the eastern portion of the California Current and the adjacent coastal upwelling region. Elevated densities were recorded for all marine bird taxa except the Leach's Storm-Petrel (Oceanodroma leucorhoa). The variance explained by the regression models ranged from 3% for the Leach's Storm-Petrel to 85% for all marine birds. The response observed is notably stronger than previous analyses with similar data.

Marine Bird Attraction to Thermal Fronts in the California Current System

I relate marine bird density to the 55 strongest thermal fronts encountered during a survey of much of the eastern portion of the California Current and the adjacent coastal upwelling region. Elevated densities were recorded for all marine bird taxa except the Leach's Storm-Petrel (Oceanodroma leucorhoa). The variance explained by the regression models ranged from 3% for the Leach's Storm-Petrel to 85% for all marine birds. The response observed is notably stronger than previous analyses with similar data.

MARINE BIRD ATTRACTION TO THERMAL FRONTS IN THE CALIFORNIA CURRENT SYSTEM

Abstract I relate marine bird density to the 55 strongest thermal fronts encountered during a survey of much of the eastern portion of the California Current and the adjacent coastal upwelling region. Elevated densities were recorded for all marine bird taxa except the Leach's Storm-Petrel (Oceanodroma leucorhoa). The variance explained by the regression models ranged from 3% for the Leach's Storm-Petrel to 85% for all marine birds. The response observed is notably stronger than previous analyses with similar data.

Particulates and the environmental capacity for trace metals: A small river as a model for a land-sea transfer system: the Raša River estuary

The paper deals with the role of particulates in the transfer of trace metals from land to sea. In the mechanisms oriented research, small rivers and their estuaries fulfil a special role by enabling identification of single processes and single transport mechanisms of general relevance to global land-sea interaction. In big rivers the complexity and the overlapping influences often prevent identification of these. Laboratory experiments often defy natural conditions. Small rivers, originating from identifiable and often unique geological regions, with a limited number of anthropogenic activities loading their watersheds, offer a real-life model system for studies of physical and physicochemical processes. The result of field work in the Raša River (Croatian Adriatic) karstic estuary and corollary laboratory experiments have shown the sedimentation pattern with the prevalent accumulation of terrigenous material in the upper estuary. The results indicate that trace metals are either of prevalently natural origin (Cr, Ti, Cd) or anthropogenically superimposed (Cu, Pb, Zn). However, most of the heavy metals accumulate in the proximity of the river mouth due to adsorption to clay minerals. Only Zn concentrations in estuarine sediments indicate its higher mobility and further transport. The results of this investigation should help in understanding the ultimate environmental capacity of the estuary and the adjacent coastal region.

Use of intracellular amino acid analysis as an indicator of the physiological status of natural dinoflagellate populations

The physiological status of 2 dinoflagellate populations in Bantry Bay, Ireland, was examined by use of amino acid analys~s. Observations were made durlng two 24 h periods. In one, during an upwelling event, the phytoplankton population was of low density (ca 1 yg chl a I ' ) and dominated mainly by Ceratium, Prorocentrum and Scrippsiella species. In the second (1 wk later), following relaxation of the upwelling and an incursion of surface water from the adjacent open coastal region, the phytoplankton community was dominated by Ceratium spp. and Gyrodiniurn aureolum with chl a concentrations up to 10 times higher. During the first sampling period, there was evidence of slight N-stress at the surface; the ratio of intracellular glutamine/glutamate (Gln/Glu) was 0.35, increasing with ammonium spiking There was evidence of C-stress at the chl maximum, where Gln/Glu was high (1.2) and decreased on exposure to increased irradiance. During the second samphng period, Gln/Glu was low (0.1) suggesting a poor N-status. However, there was little or even a negative response of Gln/Glu to ammonium splking; glutamate responded to the spiklng rather than glutamine. The general composition of the intracellular amino acid pool was similar to that at the first period, with high proportions of N-rich amino acids such as arginine. This second population appeared to be physiologically damaged in some way; this would not appear to have been simply a result of N-stress, but perhaps reflected the consequences of the associated advective process and exposure of the algae to high photon flux densities. The concentration of dissolved free a m n o acids (DFAA) during the second period was up to 4 times higher than at the first, but still dominated by serine and glycine. DFAA appeared to relate more to the presence of zooplankton than to the phytoplankton.

Analysis of global cloudiness: 1. Comparison of Meteor, Nimbus 7, and International Satellite Cloud Climatology Project (ISCCP) satellite data

In this first paper of a three‐part series on cloudiness we intercompare the simultaneous cloudiness data obtained from Meteor satellites, Nimbus 7, and the International Satellite Cloud Climatology Project (ISCCP) for the one‐year period, July 1983 to June 1984. Four versions of ISCCP cloudiness are obtained from analyses of the ISCCP‐C1 data. These versions differ in their requirements for temporal and spectral sampling. ISCCPs 1 and 2 require for each 2.5° × 2.5° latitude‐longitude cell that there be observations at least (Nd = ) 20 of the 28–31 possible days per month and at least (Nh = ) 5 of the 8 possible 3 hourly times each such day; ISCCPs 3 and 4 require only Nd = 1 and Nh = 1. ISCCPs 1 and 3 use IR information only, while ISCCPs 2 and 4 use both IR and visible (VIS) information. The ISCCP‐C2 data produced by the ISCCP Global Processing Center is also included in this intercomparison. The ISCCP 1–4 intercomparison shows that (1) the cloudiness differences due to the above temporal sampling are smaller than those due to the above spectral sampling; (2) both spectral and temporal sampling effects are larger for the northern hemisphere than for the southern hemisphere; and (3) the difference between zonal mean cloudiness with and without visible information generally increases with latitude from polar night to about 60° latitude in the summer hemisphere. The comparison between ISCCP‐C2 and ISCCP 4 cloudiness shows that (1) ISCCP‐C2 cloudiness is larger for both hemispheres and the globe; (2) ISCCP‐C2 zonal mean cloudiness is larger from 55° latitude in the winter hemisphere to 65° latitude in the summer hemisphere; and (3) ISCCP‐C2 cloudiness is larger than the ISCCP 4 cloudiness over most of the Earth, with largest differences generally located over water and the adjacent coastal regions. The comparison among Meteor, Nimbus 7, and ISCCP‐C2 cloudiness shows many features, including (1) hemispheric mean and global mean cloudiness for Nimbus 7 are smaller than for Meteor and ISCCP‐C2; (2) for Meteor, Nimbus 7, and ISCCP‐C2, mean southern hemisphere cloudiness exceeds mean northern hemisphere cloudiness in July 1983 and in January 1984; (3) for Meteor, Nimbus 7, and ISCCP‐C2, hemispheric mean cloudiness increases from winter to summer in both hemispheres, with a larger increase in the northern hemisphere; (4) for Meteor, Nimbus 7, and ISCCP‐C2, zonal mean cloudiness maxima are located in the intertropical convergence zone (ITCZ) in the summer hemisphere, in the winter hemisphere storm‐track region and same latitudinal belt in the summer hemisphere, and generally increase with decreasing latitude from about 60°N to 60°S; (5) over much of the Earth, particularly in the tropical‐subtropical minima, Nimbus 7 shows the smallest zonal mean cloudiness, with values as much as 0.4 less than those for Meteor and ISCCP‐C2; (6) the spatial cloudiness patterns and amplitudes of ISCCP‐C2 and Meteor are most alike, with correlation and regression coefficients of 0.81–0.85 and 0.81–0.90, respectively; (7) the temporal cloudiness patterns and amplitudes of ISCCP‐C2 and Nimbus 7 are most alike, with average correlation and regression coefficients of 0.70 and 0.83 for the northern hemisphere and 0.64 and 0.74 for the southern hemisphere; (8) Meteor, Nimbus 7, and ISCCP‐C2 cloudiness values show considerable disagreement in the polar regions, particularly in winter, with Nimbus 7 cloudiness exceeding both Meteor and ISCCP‐C2 cloudiness in the Antarctic during winter, Meteor cloudiness being less than both ISCCP‐C2 and Nimbus 7 cloudiness in the Arctic during winter, and ISCCP‐C2 cloudiness being less than both Meteor and Nimbus 7 cloudiness in summer in both hemispheres; and (9) both Nimbus 7 and ISCCP‐C2 show an increase in cloudiness from summer to winter over the Arctic and Antarctic, while Meteor shows a decrease. A special observational program in both the Arctic and the Antarctic is proposed to resolve the discrepancies among the satellite and ground‐based cloudiness observations in polar latitudes.