Mode Water Research Articles

Influence Mechanism of Cyanobacterial Extracellular Polymeric Substances on the Water Quality in Dynamic Water Supply System

As a kind of high-organic-content contamination source, extracellular polymeric substances (EPS) secreted by cyanobacteria have become an important factor restricting the safety of supply water. In the dynamic batch mode water supply system, cyanobacterial EPS accelerated the decay rate of residual chlorine, resulting in a 21–26 times increase of the total viable bacteria count within 72 h. The water turbidity exceeded upper limit of the standards for drinking water quality within 4 h, with an increase of 306–332% within 72 h. The biological stability was reduced with BDOC and AOC increased by 41.4–43.8% and 331–396%, respectively. The main cause is that cyanobacterial EPS act as nutrients and metabolic energy for microorganisms, promoting their metabolic activity and secretion of extracellular organic components. This leads to the metabolic accumulation of tryptophan, fulvic acids and humic acids in the pipeline, thus further promoting the regeneration of bacteria. Compared with the influence of biofilm on pipe wall caused by long-term use of water supply network, the contribution of cyanobacterial EPS to the water contamination of pipe network is increased several times. Therefore, even in the presence of residual chlorine, the secondary contamination caused by cyanobacterial EPS in the water supply system could not be neglected.

Dissolved and suspended organic matter dynamics in the Cape Verde Frontal Zone (NW Africa)

The Cape Verde Frontal Zone (CVFZ) is a highly dynamic region located in the southern boundary of the Canary Current Eastern Boundary Upwelling Ecosystem. Due to the interaction of the Cape Verde Front with the Mauritanian coastal upwelling, the area features large vertical and horizontal export fluxes of organic matter. While the flux, composition and biogeochemical role of sinking organic matter have been thoroughly studied, much less attention has been paid to the dissolved (DOM) and suspended particulate (POM) organic matter fractions. Full-depth profiles of DOM and POM were recorded during an oceanographic cruise in the CVFZ, with four consecutive transects defining a box embracing the giant filament of Cape Blanc and the Cape Verde front. The distributions of DOM and POM and their C:N stoichiometric ratios in the epipelagic layer were strongly influenced by the position of the transects relative to the giant filament and the front. Geographical heterogeneity in POM and DOM distributions and elemental composition was also observed within each of the different water masses of contrasting origin present in the area (North and South Atlantic Central Water, Subpolar Mode Water, Mediterranean Water, Antarctic Intermediate Water, Labrador Sea Water and North East Atlantic Deep Water). These facts suggest that water masses properties are re-shaped by biogeochemical processes occurring within the CVFZ. Nevertheless, our analysis indicates that DOM and POM mineralisation represents only 8.1% of the inorganic carbon and 17.8% of the inorganic nitrogen produced by the local mineralisation of organic matter. Intense lateral export of POM and DOM out of the boundaries of the CVFZ is the likely reason behind these low contributions, which confirm the prominent role of sinking fluxes of organic matter for mineralisation processes in this region. The DOM distribution in the CVFZ interior is apparently affected by the dissolution of fast sinking particles.

Covariability of Subantarctic Mode Water and the Southern Branch of the Subtropical Indian Ocean Countercurrent in Argo Observations

Covariability of Subantarctic Mode Water and the Southern Branch of the Subtropical Indian Ocean Countercurrent in Argo Observations

Role of air–sea fluxes and ocean surface density in the production of deep waters in the eastern subpolar gyre of the North Atlantic

Abstract. Wintertime convection in the North Atlantic Ocean is a key component of the global climate as it produces dense waters at high latitudes that flow equatorward as part of the Atlantic Meridional Overturning Circulation (AMOC). Recent work has highlighted the dominant role of the Irminger and Iceland basins in the production of North Atlantic Deep Water. Dense water formation in these basins is mainly explained by buoyancy forcing that transforms surface waters to the deep waters of the AMOC lower limb. Air–sea fluxes and the ocean surface density field are both key determinants of the buoyancy-driven transformation. We analyze these contributions to the transformation in order to better understand the connection between atmospheric forcing and the densification of surface water. More precisely, we study the impact of air–sea fluxes and the ocean surface density field on the transformation of subpolar mode water (SPMW) in the Iceland Basin, a water mass that “pre-conditions” dense water formation downstream. Analyses using 40 years of observations (1980–2019) reveal that the variance in SPMW transformation is mainly influenced by the variance in density at the ocean surface. This surface density is set by a combination of advection, wind-driven upwelling and surface fluxes. Our study shows that the latter explains ∼ 30 % of the variance in outcrop area as expressed by the surface area between the outcropped SPMW isopycnals. The key role of the surface density in SPMW transformation partly explains the unusually large SPMW transformation in winter 2014–2015 over the Iceland Basin.

Volume Budget of Subantarctic Mode Water in the Southern Ocean From an Ocean General Circulation Model

AbstractThe volume budget of Subantarctic Mode Water (SAMW) in the Southern Ocean (SO) is examined using a 0.1° ocean model output from 1950 to 2017. The results show that air–sea buoyancy fluxes, advective exports, and diapycnal mixing are all important to the SAMW volume budget. A climatological mean analysis finds that, for the SO as a whole, water in the SAMW density range ( kg m−3) is balanced between the following: formation due to air–sea buoyancy fluxes ( Sv), removal due to advective export northward out of the SO ( Sv), destruction due to diapycnal mixing ( Sv), and storage ( Sv). Decadal changes in the SAMW volume in the Indian and Pacific sectors display a two‐layer density structure, in which the volumes of the upper and lower layers vary predominantly out of phase with each other. In addition, the SAMW volume changes in the Indian and Pacific sectors appear to compensate each other on decadal time scales. The volume of SAMW in the SO has increased by ∼11% since the 1950s, and this increase tends to emerge gradually from denser to lighter layers. The increased SAMW volume mainly results from a consistent increase in oceanic buoyancy gain over the outcropping area at approximately 27.1 .

Diagnosing CO2 emission-induced feedbacks between the Southern Ocean carbon cycle and the climate system: A multiple Earth System Model analysis using a water mass tracking approach

AbstractAnthropogenic CO2emission-induced feedbacks between the carbon cycle and the climate system perturb the efficiency of atmospheric CO2uptake by land and ocean carbon reservoirs. The Southern Ocean is a region where these feedbacks can be largest and differ most among Earth System Model projections of 21stcentury climate change. To improve our mechanistic understanding of these feedbacks, we develop an automated procedure that tracks changes in the positions of Southern Ocean water masses and their carbon uptake. In an idealised ensemble of climate change projections, we diagnose two carbon–concentration feedbacks driven by atmospheric CO2(due to increasing air-sea CO2partial pressure difference,dpCO2, and reducing carbonate buffering capacity) and two carbon–climate feedbacks driven by climate change (due to changes in the water mass surface outcrop areas and local climate impacts). Collectively these feedbacks increase the CO2uptake by the Southern Ocean and account for one-fifth of the global uptake of CO2emissions. The increase in CO2uptake is primarily dpCO2-driven, with Antarctic intermediate waters making the largest contribution; the remaining three feedbacks partially offset this increase (by ~25%), with maximum reductions in Subantarctic mode waters. The process dominating the decrease in CO2uptake is water mass-dependent: reduction in carbonate buffering capacity in Subtropical and Subantarctic mode waters, local climate impacts in Antarctic intermediate waters, and reduction in outcrop areas in circumpolar deep waters and Antarctic bottom waters. Intermodel variability in the feedbacks is predominatelydpCO2–driven and should be a focus of efforts to constrain projection uncertainty.

Subantarctic Mode Water and its long-term change in CMIP6 models

AbstractThe Subantarctic Mode Water (SAMW) is a major water mass in the South Indian and Pacific oceans and plays an important role in the ocean uptake and anthropogenic heat and carbon. The characteristics, formation, and long-term evolution of the SAMW are investigated in the “historical” and “SSP245” scenario simulations of the sixth Coupled Models Intercomparison Project (CMIP6). Defined by the low potential vorticity, the simulated SAMW is consistently thinner, shallower, lighter, and warmer than in observations, due to biases in the winter mixed layer properties and spatial distribution. The biases are especially large in the South Pacific Ocean. The winter mixed layer bias can be attributed to unrealistic heat loss and stratification in the models. Nevertheless, the SAMW is presented better in the CMIP6 than CMIP5, regarding its volume, location, and physical characteristics. In warmer climate, the simulated SAMW in the South Indian Ocean consistently becomes lighter in density, with a reduced volume and a southward shift in the subduction region. The reduced heat loss, instead of the increased Ekman pumping induced by the poleward intensified westerly wind, dominates in the SAMW change. The winter mixed layer shoals in the northern outcrop region and the SAMW subduction shifts southward where the mixed layer remains deep. The projected reduction of the SAMW volume is likely to impact the heat and freshwater redistribution in the Southern Ocean.

Mesoscale Eddy Effects on Subduction and Transport of the North Pacific Subtropical Mode Water

Mesoscale Eddy Effects on Subduction and Transport of the North Pacific Subtropical Mode Water

The Origin and Fate of Subantarctic Mode Water in the Southern Ocean

AbstractSubantarctic Mode Water (SAMW) forms in deep mixed layers just north of the Antarctic Circumpolar Current in winter, playing a fundamental role in the ocean uptake of heat and carbon. Using a gridded Argo product and the ERA-Interim reanalysis for years 2004-2018, the seasonal evolution of the SAMW volume is analyzed using both a kinematic estimate of the subduction rate and a thermodynamic estimate of the air-sea formation rate. The seasonal SAMW volume changes are separately estimated within the monthly mixed layer and in the interior below it. We find that the variability of SAMW volume is dominated by changes in SAMW volume in the mixed layer. The seasonal variability of SAMW volume in the mixed layer is governed by formation due to air-sea buoyancy fluxes (45%, lasting from July to August), entrainment (35%), and northward Ekman transport across the Subantarctic Front (10%). The interior SAMW formation is entirely controlled by exchanges between the mixed layer and the interior (i.e. instantaneous subduction), which occurs mainly during August-October. The annual mean subduction estimate from a Lagrangian approach shows strong regional variability with hotspots of large SAMW subduction. The SAMW subduction hotspots are consistent with the distribution and export pathways of SAMW over the central and eastern parts of the south Indian and Pacific Oceans. Hotspots in the south Indian Ocean produce strong subduction of 8 and 9 Sv for the light and southeast Indian SAMW, respectively, while SAMW subduction of 6 and 4 Sv occurs for the central and southeast Pacific SAMW, respectively.

Impact of the reemergence of North Pacific subtropical mode water on the multi-year modulation of marine heatwaves in the North Pacific Ocean during winter and early spring

Marine heatwaves (MHWs), which are characterized by extremely warm water, can harm the marine ecosystem and fishing industry; improving the prediction of such events could reduce their harmful impact. In this study, we examined MHWs occurring in the North Pacific in winter/early spring, and their relationship with North Pacific subtropical mode water (STMW), based on the data analysis and numerical experiments. The time-lagged correlation between the cumulative intensity of MHWs and volume of STMW in March of each year suggests that STMW can modulate MHWs for up to three years after its formation. A patch of statistically significant negative correlation initially appeared in the formation region of the STMW but was found to the east of it near the Transition Zone Chlorophyll Front (TZCF) after one year. This patch stagnated near this remote site in the second winter and early spring. Passive tracer experiments using a numerical model indicate that the STMW, formed near the Kuroshio Extension in March, moves to the east underneath the mixed layer and is entrained to the surface in the following winter while altering the properties of STMW. The STMW reemerges in the second winter, after stagnating under the mixed layer near the TZCF. This suggests that the reemergence of STMW can suppress MHWs in the North Pacific during winter and early spring by reducing the sea surface temperature; if the volume of STMW is anomalously low, there is a greater likelihood of the occurrence of MHWs near the TZCF in the following two winters and early springs. Our results indicate that understanding STMW formation is crucial for predicting MHWs in the North Pacific Ocean during winter and early spring.

Southeast Indian Subantarctic Mode Water in the CMIP6 Coupled Models

AbstractThis study assesses the capability of 12 models in the Phase 6 of the Coupled Models Intercomparison Project (CMIP6) in simulating the Southeast Indian Subantarctic mode water (SEISAMW) by comparing to Argo observations. The results show that all of the analyzed CMIP6 coupled models can reproduce the SEISAMW and its seasonal cycle, albeit with discrepancies of formation region and properties among the models. The SEISAMW subduction rate shows significant interannual variability, which is primarily induced by lateral induction in these models, in agreement with observations. Furthermore, the longterm trends of the SEISAMW show volume loss in accordance with the descending trend of the subduction rate, which are co‐occurred with the ascending trend of the Southern Annular Mode (SAM) indices in most of the analyzed CMIP6 models, similar to those in the CMIP3 and CMIP5 coupled models. Meanwhile, the potential density of the SEISAMWs show decreasing trends in these volume loss models, which could be explained by the warming (SAM0‐UNICON, CESM2‐WACCM, CAS‐ESM2‐0 and CIESM), the freshening (IPSL‐CM6A‐LR, CAMS‐CSM1‐0, MRI‐ESM2‐0, and FGOALS‐f3‐L) or the both (FIO‐ESM‐2‐0, E3SM‐1‐0, and CanESM5) trends of the SEISAMWs in different CMIP6 coupled models. Decreases in the projected subduction rate and volume of SEISAMW imply a slowdown of Southern Indian Ocean circulation in the future, reducing the heat and carbon transport from atmosphere to ocean interior contributed by SEISAMW.

Subtropical Mode Water in a recent persisting Kuroshio large-meander period: part I\u2014formation and advection over the entire distribution region

Since August 2017, the Kuroshio has taken a large-meander (LM) path, which has forced the Kuroshio extension (KE) to be in its stable state against its wind-forced decadal variability. How such current conditions have impacted the formation and advection of North Pacific subtropical mode water (STMW) over its distribution region was examined using Argo float data during 2005–2020. Out of the whole STMW defined as a low-potential vorticity layer of 16–19.5 ºC, a relatively cold variety of 16–18 ºC, which was formed south of the KE and advected westward and southward, occupied more than 80% of the total volume. The formation rate of the 16–18 ºC variety was low during 2006–2009 in an unstable-KE period and high during 2010–2015 in a stable-KE period, and then dropped drastically in 2016 despite the KE still being in the stable state. After a short unstable-KE period in 2016–2017, the LM-forced, stable-KE period began, but the formation rate of the 16–18 ºC variety has not restored, possibly due to stronger background stratification propagated from the central North Pacific. In addition, the 16–18 ºC variety has had to make a southern detour around the LM, and its westward advection from the formation region south of the KE to the region south of Japan has been significantly decreased, possibly because it is dissipated more strongly over a southern part of the Izu–Ogasawara Ridge. Due to such decline in the formation and advection, the volume of the 16–18 ºC variety and hence that of the whole STMW have gradually decreased since 2016.

Tracking Southern Ocean Sea Ice Extent With Winter Water: A New Method Based on the Oxygen Isotopic Signature of Foraminifera

AbstractSouthern Ocean sea ice plays a central role in the oceanic meridional overturning circulation, transforming globally prevalent watermasses through surface buoyancy loss and gain. Buoyancy loss due to surface cooling and sea ice growth promotes the formation of bottom water that flows into the Atlantic, Indian, and Pacific basins, while buoyancy gain due to sea ice melt helps transform the returning deep flow into intermediate and mode waters. Because northward expansion of Southern Ocean sea ice during the Last Glacial Maximum (LGM; 19–23 kyr BP) may have enhanced deep ocean stratification and contributed to lower atmospheric CO2 levels, reconstructions of sea ice extent are critical to understanding the LGM climate state. Here, we present a new sea ice proxy based on the 18O/16O ratio of foraminifera (δ18Oc). In the seasonal sea ice zone, sea ice formation during austral winter creates a cold surface mixed layer that persists in the sub‐surface during spring and summer. The cold sub‐surface layer, known as winter water, sits above relatively warm deep water, creating an inverted temperature profile. The unique surface‐to‐deep temperature contrast is reflected in estimates of equilibrium δ18Oc, implying that paired analysis of planktonic and benthic foraminifera can be used to infer sea ice extent. To demonstrate the feasibility of the δ18Oc method, we present a compilation of N. pachyderma and Cibicidoides spp. results from the Atlantic sector that yields an estimate of winter sea ice extent consistent with modern observations.

The Impact of Southern Ocean Ekman Pumping, Heat and Freshwater Flux Variability on Intermediate and Mode Water Export in CMIP Models: Present and Future Scenarios

AbstractSubduction in the Antarctic circumpolar region of the Southern Ocean (SO) results in the formation of Antarctic Intermediate Water (AAIW) and Subantarctic Mode Water (SAMW). Theoretical understanding predicts that subduction rates of these waters masses is driven by wind stress curl and buoyancy fluxes. The objective of this work is to evaluate the extent to which AAIW and SAMW variability are correlated to SO air‐sea fluxes and how potential changes to those forcings would impact the future water mass export rates. We correlate the water mass volume transport at 30°S with Ekman pumping, freshwater and heat fluxes in the Coupled Model Intercomparison Project. The export of these water masses varies across models, with most overestimating the total transport. Correlation coefficients between the air‐sea fluxes and exports are consistent with theoretical expectations. In the picontrol/historical scenarios, the highest correlations with AAIW export variability are heat flux, while Ekman pumping best explains SAMW. However, multivariate regressions show that both AAIW and SAMW export variability are better explained using the combination of all three fluxes. In future scenario simulations air‐sea fluxes trend significantly in the catastrophic scenario (RCP8.5 and SSP8.5). Both AAIW and SAMW are still highly correlated to the fluxes, but with different correlation coefficients. The dominant forcing components even change from the present simulations to the future scenario runs. Thus, correlations between AAIW and SAMW transports and air‐sea fluxes are not stationary in time, limiting the predictive skill of statistical models and highlighting the importance of using complex climate models.

Intensified organic carbon burial on the Australian shelf after the Middle Pleistocene transition

The Middle Pleistocene Transition (MPT) represents a major change in Earth's climate state, exemplified by the switch from obliquity-dominated to ∼100-kyr glacial/interglacial cycles. To date, the causes of this significant change in Earth's climatic response to orbital forcing are not fully understood. Nonetheless, this transition represents an intrinsic shift in Earth's response to orbital forcing, without fundamental changes in the astronomical rhythms. This study presents new high-resolution records of International Ocean Discovery Program (IODP) Site U1460 (eastern Indian Ocean, 27°S), including shallow marine productivity and organic matter flux reconstructions. The proxy series covers the interval between 1.1 and 0.6 Ma and provides insights into Pleistocene Leeuwin Current dynamics along the West Australian shelf. The large >45 m global sea level drop during the marine isotope stage (MIS) 22–24 is marked in our data, suggesting that the MPT led to large-scale changes in Indian Ocean circulation patterns and surface water conditions. We consider shelf exposure (and thus the “Sahul-Indian Ocean Bjerknes mechanism”) as a possible key process to increase the upwelling of nutrient-rich sub-Antarctic Mode waters through the Leeuwin Undercurrent along the Australian shelf. We conclude that the shoaling of nutrient-rich lower-thermocline waters enhanced mid-latitude productivity patterns in the eastern Indian Ocean across the 900-ka event.

Spiciness Anomalies of Subantarctic Mode Water in the South Indian Ocean

AbstractThis study investigates spreading and generation of spiciness anomalies of the Subantarctic Mode Water (SAMW) located on 26.6 to 26.8 σθ in the south Indian Ocean, using in situ hydrographic observations, satellite measurements, reanalysis datasets, and numerical model output. The amplitude of spiciness anomalies is about 0.03 psu or 0.13°C and tends to be large along the streamline of the subtropical gyre, whose upstream end is the outcrop region south of Australia. The speed of spreading is comparable to that of the mean current, and it takes about a decade for a spiciness anomaly in the outcrop region to spread into the interior up to Madagascar. In the outcrop region, interannual variability in mixed layer temperature and salinity tends to be density compensating, which indicates that Eulerian temperature or salinity changes account for the generation of isopycnal spiciness anomalies. It is known that wintertime temperature and salinity in the surface mixed layer determine the temperature and salinity relationship of a subducted water mass. Considering this, the mixed layer heat budget in the outcrop region is estimated based on the concept of effective mixed layer depth, the result of which shows the primary contribution from horizontal advection. The contributions from Ekman and geostrophic currents are comparable. Ekman flow advection is caused by zonal wind stress anomalies and the resulting meridional Ekman current anomalies, as is pointed out by a previous study. Geostrophic velocity is decomposed into large-scale and mesoscale variability, both of which significantly contribute to horizontal advection.

Buoyancy and Wind Driven Changes in Subantarctic Mode Water During 2004–2019

AbstractThe Subantarctic Mode Water (SAMW) is a thick low‐stratified subsurface water mass located north of the Antarctic Circumpolar Current, and it is important for heat uptake. How the SAMW has changed and what drives that change remain to be quantified. By synthesizing observations, eddy‐resolving ocean model hindcasts and climate model simulations, we show that the SAMW has become warmer, fresher, lighter, and weaker in recent decades. As revealed by partially coupled model experiments, the SAMW core has remained at a constant depth since 2004 due to a balance between the enhanced wind stress curl, which deepens the SAMW core, and the buoyancy gain, which shallows the core. The lightening and weakening of the SAMW mainly result from the increased surface buoyancy gain due to climate warming, while the enhanced westerlies play a secondary role in slowing this trend. As greenhouse warming continues, the increased stratification will keep weakening the SAMW.

Changes in the Subantarctic Mode Water Properties and Spiciness in the Southern Indian Ocean based on Argo Observations

AbstractThe Subantarctic Mode Water (SAMW) plays an essential role in the global heat, freshwater, carbon, and nutrient budgets. In this study, decadal changes in the SAMW properties in the Southern Indian Ocean (SIO) and associated thermodynamic and dynamic processes are investigated during the Argo era. Both temperature and salinity of the SAMW in the SIO show increasing trends during 2004-2018. A two-layer structure of the SAMW trend, with more warm and salty light SAMW but less cool and fresh dense SAMW, is identified. The heaving and spiciness processes are important but have opposite contributions to the temperature and salinity trends of the SAMW. A significant deepening of isopycnals (heaving), peaking atσθ=26.7-26.8 kg m−3in the middle layer of the SAMW, expands the warm and salty light SAMW and compresses the cool and fresh dense SAMW corresponding to the change in subduction rate during 2004-2018. The change in the SAMW subduction rate is dominated by the change in the mixed layer depth, controlled by the changes in wind stress curl and surface buoyancy loss. An increase in the mixed-layer temperature due to weakening northward Ekman transport of cool water leads to a lighter surface density in the SAMW formation region. Consequently, density outcropping lines in the SAMW formation region shift southward and favor the intrusion and entrainment of the cooler and fresher Antarctic surface water from the south, contributing to the cooling/freshening trend of isopycnals (spiciness). Subsequently, the cooler and fresher SAMW spiciness anomalies spread in the SIO via the subtropical gyre.

Polyvinyl alcohol hydrogel-supported forward osmosis membranes with high performance and excellent pH stability

A new class of a polyvinyl alcohol (PVA) hydrogel support was used to fabricate a forward osmosis (FO) membrane with high performance and excellent pH resistance. The intrinsically hydrophilic PVA support formed by non-solvent-induced phase separation and subsequent crosslinking exhibited a thin (∼40μm) and highly porous scaffold-like structure with high pore interconnectivity, achieving a considerably low structural parameter (∼184μm). Toluene-assisted interfacial polymerization was also employed to fabricate a polyamide (PA) selective layer with high water permeance and salt selectivity on the prepared hydrophilic PVA support. The fabricated PVA supported-thin film composite (PVA-TFC) membrane exhibited 2.7–3.7 times higher FO mode water flux and 70–78% lower specific salt flux than commercial FO membranes with a draw solution of 1.0M NaCl and a feed solution of DI water. The PVA-TFC membrane also outperformed other previously reported FO membranes. In addition, the PVA-TFC membrane had superior pH resistance when compared with commercial FO membranes, which is imparted by the excellent pH stability of both its PA selective layer and PVA support. Our strategy paves the way for the fabrication of high-performance and pH-resistant FO membranes that can be employed in harsh water environments.

Exploring the impacts of religious tourism on development: (A case study of Redemption Camp, Mowe, Ogun State, Nigeria)

The Redemption Camp is unarguably one tourism destination that has fascinated many among the Christian and non-Christian folks. Religious sites are among the most visited tourism destinations in the world; people have visited Redemption Camp in their thousands and millions in recent times more than any known tourism destination in Nigeria. The evidence for these realities is attributed to the selfsustainable status the Camp has attained over the years and the increased rate at which it continues to attract visitors. Development in terms of infrastructure and socio-economic activities in Redemption Camp and the neighbouring host communities is evident, arising primarily from tourism activities. This reality underpins the impacts of religious tourism on the development. The study x-rays development, as enhanced by the activities of religious tourism in the Redemption Camp, Mowe, Ogun State, Nigeria. The research employs participant observation, unstructured interviews and key informants interviews. The key informant interviews elicited facts on Redemption Camp as a religious tourism destination while the unstructured interviews examined visitors’ attitude as religious tourists. The study specifically identifies the role religious tourism played and is still in the development of Redemption Camp as wellas the spill over effects on the residents and the host communities. Factors that enhanced religious tourism activities in the Camp include the provision of efficient transportation mode, stable electricity, comfortable accommodation and clean water supply. Tourismattractions within the camp which have earned the camp its self-sustaining reputation are: the Redemption Resort, The Redeemer’s High School. Redeemer’s Maternity Centre, Banking Institutions, Open Heavens International Centre, Emmanuel Park and the main auditorium which sits over two million attendees. It is recommended that, with the growing spate of expansionary activities in the Redemption Camp, the management should ensure necessary precautionary measures in place to guard against disrupting the environmental harmony the redemption camp is known for.
 Key words: Tourism, Religious tourism, Development, Redemption Camp