With unprecedented rate of development in the countries surrounding the gulfs of the Arabian Sea, there has been a rapid warming of these gulfs. In this regard, using Advanced Very High Resolution Radiometer (AVHRR) data from 1985 to 2009, a climatological study of Sea Surface Temperature (SST) and its inter annual variability in the Persian Gulf (PG), Gulf of Oman (GO), Gulf of Aden (GA), Gulf of Kutch (KTCH), Gulf of Khambhat (KMBT), and Red Sea (RS) was carried out using the normalized SST anomaly index. KTCH, KMBT, and GA pursued the typical Arabian Sea basin bimodal SST pattern, whereas PG, GO, and RS followed unimodal SST curve. In the western gulfs and RS, from 1985 to 1991-1992, cooling was observed followed by rapid warming phase from 1993 onwards, whereas in the eastern gulfs, the phase of sharp rise of SST was observed from 1995 onwards. Strong influence of the El Niño and La Niña and the Indian Ocean Dipole on interannual variability of SST of gulfs was observed. Annual and seasonal increase of SST was lower in the eastern gulfs than the western gulfs. RS showed the highest annual increase of normalized SST anomaly (+0.64/decade) followed by PG (+0.4/decade).
In today’s era, one of the greatest challenges faced by humankind is “global warming.” There has been a 0.6°C increase in global temperature in the last century, and it is projected to further increase by 1.8°C to 4°C in the 21st century [
In the Indian context, the recent finding, that amongst the oceans, the warming of the Indian Ocean is second highest [
In this regard, the present work was taken up to study the monthly, seasonal, and annual pattern of Sea Surface Temperature (SST) and to analyse its changing pattern with emphasis on interannual variability in the eastern (Gulf of Kutch and Gulf of Khambhat) and the western gulfs (Persian Gulf, Gulf of Oman, and Gulf of Aden) of the Arabian Sea and the Red sea.
The gulfs of the Arabian Sea basin (Figure
(a) Area of Study showing Arabian Sea basin. (b) Persian Gulf. (c) Gulf of Oman. (d) Gulf of Aden. (e) Red Sea. (f) Gulf of Kutch and Gulf of Khambhat.
The Persian Gulf (24–3°N; 48–56.5°E), (Figure
In the Persian Gulf, the seasonal differences of insolation, along with cold winds from the nearby highlands, result in extreme temperature (ranging from 16°C to 35°C) [
The Gulf of Oman (22°3–26°5′N; 56.5–61°43′E) is a strait connecting the Arabian Sea with the Persian Gulf (Figure
Some of the most powerful eddy currents of the Arabian Sea are located close to the Omani coast. The coastal areas of the Gulf of Oman support varied habitats including mangrove swamps, lagoons, and mudflats.
The Gulf of Aden (GA) (10°–15°N; 43°–52°E), connecting the Red Sea with the Arabian Sea, is part of the Suez Canal shipping route between the Mediterranean Sea and the Indian Ocean (Figure
The Red Sea (RS) (12°29′N–27°57′N; 34°36′E–43°30′E) is approximately 2,100 km long and 280 km wide (Figure
The waters of the Red Sea are warm and saline. The temperature ranges from 21°C–28°C in the north and 26°C to 32°C in the south. Salinities in the Red Sea range from 37% in the south to 42% in the north. A consequence of these extreme conditions is that some species within the Red Sea (like mangroves, shallow sea grasses, etc.) probably exist at the limits of their physiological tolerance [
The Gulf of Kutch (22°15′–23°4′N; 68°20′–70°40′E) encloses an area of 7350 km2 (Figure
The Gulf of Kutch is one of India’s only coastal areas endowed with coral reefs. It provides a platform for different habitats like coral reefs, mangroves, creeks, mud flats, islands, rocky shore, sandy shore, and so forth and hence is enriched in biodiversity [
Gulf of Khambhat (between 72°2′E to 72°6′E and 21° to 22°2′N) is one of the major fishing areas along western coast of India (Figure
The regional effect of the global warming in the oceanic water masses needs to be assessed and quantified. However, the lack of uniform data and methodology hampers such regional analysis [
In this study the monthly NOAA AVHRR Pathfinder (version 5.0) SST data at 4 km resolution was obtained from NASA’S Jet Propulsion Laboratory’s Physical Oceanographic Centre (
For each of the defined areas of study, the monthly images were masked to avoid the influence of the land and clouds using the image processing software ENVI 4.1 and ERDAS 9.0. For analysis all the pixels of the study area were included. Care was taken to exclude the pixels with zero values while averaging. Following Joint Global Ocean Flux Study (JGOFS) [ northeast monsoon (December–March) (NEM), spring intermonsoon (April-May) (SIM), southwest monsoon (June–September) (SWM), and fall intermonsoon (October-November) (FIM).
The climatological mean (CM25) of 25 years (1985–2009) for each month was calculated by averaging the monthly mean (
Figure
Comparison of the monthly climatological mean SST (1985–2009) of the Persian Gulf, Gulf of Oman, Red Sea, Gulf of Aden, Gulf of Kutch, and Gulf of Khambhat with Arabian Sea open ocean.
The Gulf of Aden and the eastern gulfs of the Arabian Sea, namely, Gulf of Kutch and Gulf of Khambhat followed the typical bimodal SST pattern as in the Arabian Sea. However, unlike the Arabian Sea open ocean where the minimum SST is observed during the months of July-August (SWM season), the minimum SST in these gulfs was found in the month of January (NEM season). In the bimodal pattern, the observed second peak of SST in the Gulf of Kutch and Gulf of Khambhat was in the month of October, similar to the Arabian Sea open ocean pattern, but in the Gulf of Aden, the second peak of SST was observed in the month of September. Climatologically, from November to April, Gulf of Aden was cooler than the Arabian Sea open ocean (by an average 1°C), while from May to October, it was warmer than the Arabian Sea open ocean (by an average 2.02°C). Climatologically, both the eastern gulfs were cooler than the Arabian Sea open ocean (by an average difference of 1.32°C and 0.38°C, resp.), for all the months, except for September and October. Besides, in the months of July and August Gulf of Kutch was found to be cooler than Arabian Sea open ocean months by more than 2°C, whereas in Gulf of Khambhat no such significant difference was found.
The Persian Gulf, Gulf of Oman, and the Red Sea exhibited a distinct unimodal SST curve instead of the typical bimodal pattern as in the Arabian Sea open ocean, with minimum temperature during the NEM season and maximum temperature during the SWM season. Whereas the minimum temperature for these three water bodies was in February, the maximum temperature in the Persian Gulf and the Red sea was in August, whereas in the Gulf of Oman, the maximum temperature was in the month of June. Climatologically from November to May, the Persian Gulf, Gulf of Oman, and the Red sea were found to be cooler than the Arabian Sea open ocean (by an average 4.9°C, 2.2°C, and 1.9°C, resp.), while from June to October they were warmer than the Arabian Sea open ocean (by an average 3.7°C, 2.7°C and 2.08°C, resp.). Amongst the eastern and western gulfs of the Arabian Sea and the Red Sea, the Persian Gulf exhibited the highest range of SST (11.97°C).
A time series study of the interannual variability of SST can be seen from Figure
Comparison of the annual normalised SST anomaly from 1985 to 2009 of the Persian Gulf, Gulf of Oman, Red Sea, Gulf of Aden, Gulf of Kutch, and Gulf of Khambhat.
A remarkable time lag in the rise of annual SST was found between the eastern and the western gulfs of the Arabian Sea and the Red Sea. For the western gulfs of the Arabian Sea and the Red Sea, a sharp increase in the annual SST was observed from 1992-1993 to 2009. However, for the eastern gulfs, the warming was delayed till 1995, and hence instead of 1992-1993, the sharp rise of annual SST was found from 1995 onwards.
For the Persian Gulf, Gulf of Oman, and Gulf of Aden, a decrease in annual normalized anomaly (cooling) was observed from 1985 to 1991, and thereafter from 1992 to 2009, a sharp increase (warming) was found. In the Persian Gulf, the normalized anomaly decreased (by −1.61), from −0.25 in the 1985 to −1.36 in 1991 and thereafter increased (by +1.48) to +0.12 in 2009. In the Gulf of Oman normalized anomaly decreased (by −1.0) from −0.44 (1985) to −1.44 (1991) and later increased (by +1.0) to +0.45 (2009). However, in the Red Sea, the normalized anomaly decreased from 1985 to 1992, (instead of 1991), from −0.76 (1985) to −1.53 (1992), and thereafter increased to +0.64 (2009).
In the Gulf of Kutch and Gulf of Khambhat (eastern gulfs of the Arabian Sea), a significant decrease in normalized anomaly (cooling) was observed from 1985 to 1994, and thereafter from 1995 to 2009 a sharp increase in normalized anomaly (warming) was found. In the Gulf of Kutch and Gulf of Khambhat, the normalized anomaly decreased from −0.10 in 1985 to −0.92 in 1994 and subsequently increased to +0.75 in 2009. Similarly, in the Gulf of Khambhat the normalized anomaly decreased from −0.22 in 1985 to −0.75 in 1994 and later increased to +0.58 in 2009.
In the three western gulfs of the Arabian Sea, namely, Persian Gulf, Gulf of Oman, and Gulf of Aden, the maximum negative normalized SST anomaly was observed in 1991 (−1.36, −1.44, and −1.16, resp.). In the Red Sea the maximum negative normalized SST anomaly was found in 1992 (−1.5). On the other hand in both the eastern gulfs of the Arabian Sea, maximum negative normalized SST anomaly was observed in 1994 (−0.93 in Gulf of Kutch and −0.75 in Gulf of Khambhat). The maximum positive normalized SST anomaly was found to be in 1998 in Gulf of Aden (+1.54), in 1999 in Persian Gulf (+1.1), in 2001 in Red Sea (+1.1), and in 2002 in Gulf of Gulf of Oman, whereas in both the eastern gulfs of the Arabian Sea, maximum positive normalized anomaly was observed in 2007.
In the western gulfs of Arabian Sea and the Red Sea, the influence of the El Niño and the La Niña events can be seen from the crest and the troughs of the graph depicting the annual SST anomaly. For instance the La Niña years like 1985, 1986, 1989, 1996, 1999, 2000, and 2008 were found to have a high negative anomalies (cooling), and the El Niño years like 1986, 1988, 1991–1995, 1997-1998, 2002, 2006, and 2009 were observed to have a high positive normalized anomalies (warming). However, the influence of the El Niño and La Niña varied in terms of the difference in magnitude of the positive and negative anomalies. Besides, in the eastern gulfs of the Arabian Sea, only few of the El Niño (namely, 1987, 1988, 2002, and 2006) or La Niña (namely, 1989 and 2008) events influenced the warming or cooling of the gulfs.
The interannual variation of SST during the four seasons, namely, northeast monsoon (NEM) (December–March), spring intermonsoon (SIM) (April-May), southwest Monsoon (SWM) (June–September), and fall inter Monsoon (FIM) (October-November), affecting the gulfs of Arabian Sea and the Red sea, was analyzed using the normalized SST anomaly indices as in Figure
Comparison of the seasonal normalised SST anomaly from 1985 to 2009 of the Persian Gulf, Gulf of Oman, Red Sea, Gulf of Aden, Gulf of Kutch, and Gulf of Khambhat. (a) Northeast monsoon (NEM) (December–March), (b) spring intermonsoon (SIM) (April-May), (c) southwest monsoon (SWM) (June–September), and (d) fall intermonsoon (FIM) (October-November).
NEM
SIM
SWM
FIM
As seen from Figures
During the northeast monsoon (NEM) (December–March), (Figure
During the spring intermonsoon (SIM) (April-May) (Figure
During the southwest monsoon season (SWM) (June–September) (Figure
During the fall intermonsoon (FIM) (October-November), an increasing trend of the normalized anomalies for the eastern and the western gulfs of the Arabian Sea and the Red sea (Figure
The influence of El Niño and La Niña on the interannual SST pattern during different seasons was observed. However, not all the warming and cooling events had similar effect on the SST anomaly. Besides, the geographical location of the particular gulf also played a crucial role in determining the impact of the ENSO.
The coefficient of variation (CV) gives the magnitude of the interannual variability. CV values of the annual and seasonal SST of the eastern and the western gulfs of the Arabian Sea and the Red Sea showed large variation amongst these water bodies as seen in Table
% Coefficient of variation for annual and seasonal SST.
Gulf/Sea | Annual | NEM | SIM | SWM | FIM |
---|---|---|---|---|---|
Persian Gulf |
18.02% | 7.88% | 11.77% | 2.68% | 7.77% |
Gulf of Oman |
11.1% | 3.85% | 8.37% | 1.93% | 4.61% |
Red Sea |
8.02% | 3.56% | 4.65% | 2.76% | 3.83% |
Gulf of Aden |
6.37% | 2.20% | 4.68% | 2.63% | 3.84% |
Gulf of Kutch |
9.35% | 5.06% | 3.63% | 10.07% | 3.14% |
Gulf of Khambhat | 6.5% | 4% | 2.13% | 4.90% | 2.83% |
The largest variation in annual SST was found in the Persian Gulf (mean CV of 18.02%), followed by the Gulf of Oman (mean CV of 11.1%), whereas Gulf of Aden was least variable (mean CV of 6.37%). The interannual variability in seasonal mean SST was highest in the Persian Gulf in all the seasons except for the SWM season. During SWM season, the maximum variability was observed to be in the Gulf of Kutch (mean CV of 10.07%) followed by Gulf of Khambhat (mean CV of 4.9%). Gulf of Aden and Gulf of Oman were least variable during the NEM and SWM seasons, whereas Gulf of Khambhat was least variable during SIM and FIM seasons.
The El Niño/Southern Oscillation (ENSO) is a phenomenon that integrates both atmospheric and oceanic parameters and is measured by various indices like the Southern Oscillation Index (SOI), Multivariate ENSO Index (MEI), Nino 3.4, and so forth. [
Comparison of normalised SST anomaly of (a) Persian Gulf, (b) Gulf of Oman, (c) Gulf of Aden, (d) Red Sea, (e) Gulf of Kutch, and (f) Gulf of Khambhat, from 1985 to 2009 along with Multivariate ENSO Index (MEI).
Besides ENSO, the Indian Ocean Dipole (IOD) is also known to be affecting the interannual SST anomalies. One phase of the IOD (positive IOD or PIOD) causes a cooling of SST in the eastern tropical Indian Ocean, while the western tropical Indian Ocean (western Arabian Sea) tends to experience a warming of sea surface temperatures. The other phase (negative IOD or NIOD) in contrast involves high SST in the eastern Indian Ocean and low in the west [
The major El Niño events of 1986-1987, 1991-1992, 1997-1998, 2002-2003, 2006-2007, and 2009-2010 and the La Niña events of 1988-1989, 1998-1999, 2000-2001, and 2007-2008 are evident from the peaks and troughs of the MEI values, with positive MEI values indicating a warming event (El Niño) and the negative MEI value indicating a cooling event (La Niña). The influence of the ENSO on SST of the Gulfs of the Arabian Sea can be clearly seen. However, one to one connection was not found. Besides, not all the El Niño or La Niña events had similar impact in the eastern and the western gulfs of the Arabian Sea. For example, the El Niño of 1991-1992 and 1994-1995 did not influence the eastern gulfs of the Arabian Sea as compared with the one of 1997-1998. The year 1997-1998 was also a positive IOD year. Hence, the extent of warming especially in the western gulfs of the Arabian Sea and the Red Sea was high. Besides, in 1992, a high negative anomaly in the western gulfs and the Red Sea was observed, owing to the influence of the negative IOD. Moreover, the impact of an IOD was seen more in the western domains of the Arabian Sea. During the extended El Niño of 1991–1995, the normalized positive SST anomaly increased remarkably in all the gulfs except the Gulf of Kutch and Gulf of Khambhat. Similarly, the stronger El Niño of 1997-1998 had a major impact on all gulfs except for the Gulf of Kutch. However, a delayed effect was observed in the Persian Gulf, Gulf of Oman, and Red Sea with peaks of normalised anomalies in 1998-1999. The La Niña of 1988-1989 resulted in cooling of Gulf of Oman, Red Sea, and Gulf of Aden but had no influence in the Gulfs of Kutch and Khambhat, whereas the La Niña of 2008 affected all the gulfs except for the Red Sea.
Time series studies of the oceanographic parameters are useful for understanding seasonal, interannual, and decadal impact of climate change. Numerous investigations have been conducted in the Arabian Sea basin to study the effect of global warming. Rupa Kumar et al. [
However, as the gulfs of the Arabian Sea have unique oceanographic features and are quite distinct from the open ocean, it becomes essential to study them individually. These gulfs are single water masses, and therefore studies conducted in few of the coastal areas cannot be generalized for the whole of the gulfs. In the present study, a comparative analysis of SST in different months and seasons was carried out for the eastern and western gulfs of the Arabian Sea and the Red Sea from 1985 to 2009 to study the regional effect of the warming of the Arabian Sea. Annually the SST has increased significantly in all the western gulfs of the Arabian Sea and the Red sea, with maximum increase of normalized SST anomaly in the Red sea (0.64/decade) and the Persian Gulf (0.40/decade). However, the increase was not significant for the eastern gulfs of the Arabian Sea (Gulf of Kutch and Gulf of Khambhat).
The analysis by Kumar et al. [
Annually for western gulfs of the Arabian Sea, that is, the Persian Gulf, Gulf of Oman, and Gulf of Aden, cooling was observed from 1985 to 1991, and thereafter from 1992 to 2009, warming was found. Whereas in the eastern gulfs of the Arabian Sea, that is, the Gulf of Kutch and Gulf of Khambhat, a significant cooling was observed from 1985 to 1994, and thereafter from 1995 to 2009, a sharp increase in normalized anomaly was found. In the three western gulfs of the Arabian Sea, (Persian Gulf, Gulf of Oman, and Gulf of Aden), the maximum negative normalized SST anomaly was observed in 1991. In the Red Sea the maximum negative normalized SST anomaly was found in 1992 (negative IOD). On the other hand in both the eastern gulfs of the Arabian Sea, maximum negative normalized SST anomaly was observed in 1994. In the western gulfs of Arabian Sea and the Red Sea, 1997-1998, 1999, 2001, 2002, 2006, 2007, and 2009 were the years with high positive normalized SST anomalies, whereas in the eastern gulfs of the Arabian Sea, the years 2002, 2007, and 2009 showed strong positive SST anomalies. Most of these years are reported to be the El Niño years like 1997-98, 2002, 2006, and 2009 which affected the SST variability pattern.
The seasonal SST analysis for the western gulfs of the Arabian Sea and the Red Sea showed an increasing trend of SST in all the four seasons. However, in the eastern gulfs of the Arabian Sea during the SWM season, cooling was observed. During the NEM and the SIM seasons, similar interannual SST variability pattern was observed in the Persian Gulf, Gulf of Oman, and the Red Sea on one hand and Gulf of Aden, Gulf of Kutch and Gulf of Khambhat on the other. During the SWM and FIM seasons similar interannual SST variability pattern was in the eastern gulfs of Arabian Sea on one hand and the western gulfs of Arabian Sea and the Red Sea on the other.
During the NEM season, in the Persian Gulf, Gulf of Oman, and the Red Sea, an alternate cycle of cooling and warming phases was observed from 1986 to 1992, 1992 to 1999, 1999 to 2005, and 2005 to 2009, whereas in the eastern gulfs of the Arabian Sea and the Gulf of Aden, the alternate cycle of cooling and warming phases was observed from 1986 to 1990, 1990 to 1995 (1997 in Gulf of Aden), 1995 to 2001-2002 (2003 in Gulf of Aden), 2001-2002 to 2005, and 2005 to 2009. The Persian Gulf, Gulf of Oman, and the Red Sea exhibited maximum cooling during 1992, owing to the negative IOD. During the NEM season, the years 1987, 1989, and 2008 showed the influence of La Niña, with high negative SST anomalies in the western gulfs of the Arabian Sea and the Red Sea. But in the eastern gulfs of the Arabian Sea, only the influence of La Niña of 2008 was visible. Similarly of all the El Niño years, 1991–1995, 2002, and 2006 resulted in a higher positive SST anomaly in the eastern and the western gulfs of the Arabian Sea and the Red sea.
Similarly, during the SIM season, alternate warming and cooling phases were noticed in the eastern gulfs of the Arabian Sea and the Gulf of Aden from 1985 to 1991-1992, 1991-1992 to 1998, 1998 to 2004-2005 (2003 for Gulf of Aden) and 2004-2005 to 2009. In the eastern gulfs of the Arabian Sea, the maximum positive SST anomaly during SIM was in 2002 that was an El Niño year. Amongst the rest of the western gulfs of the Arabian Sea and the Red Sea, the alternate phases of warming and cooling were observed from 1985 to 1991-1992, 1991-1992 to 2001, 2001 to 2005, and 2005 to 2009. The maximum negative deviation of SST from the climatological mean in the Red Sea, Gulf of Aden, Gulf of Kutch, and Gulf of Khambhat was in 1992, owing to the negative IOD. During the SIM, the influence of El Niño of 1991–1995, 1997-1998, 2002 and 2009 and La Niña of 1987 and 1989 could be seen on the SST anomalies of the eastern and the western gulfs and the Red Sea.
In the SWM season, the periods of warming and cooling included 1985 to 1987-1988, 1987-1988 to 1990-1991, 1991 to 1995 (1998 for the western gulfs and the Red Sea), 1995 to 2003, and 2003 to 2009. The Persian Gulf and the Red Sea showed positive SST anomalies in all the years from 1993 to 2009. The years with strong positive SST anomaly were 1995, 1997, 1998, and 2002 in the Gulf of Aden; 1995, 1997, 1998, 2001, 2007, and 2009 in the Red Sea; 1998, 2002 and 2006 in the Persian Gulf; and 1987 and 1993 in the Gulf of Kutch; and 1987 in the Gulf of Khambhat, of which most of the years like 1995, 1997, 1998, 2002, 2006, and 2009 were the El Niño years. However the influence of La Niña was not seen during SWM season. The years with negative SST anomalies included 1985, 1991, and 1994 in the Gulf of Aden; 1985, 1989, 1990, and 1991 in the Red Sea; 1991 in the Persian Gulf; 1989, 1991, and 2003 in the Gulf of Oman; 2001 and 2003 in the Gulf of Kutch and the Gulf of Khambhat.
During the FIM season, an increasing trend of the normalized anomalies for the eastern and the western gulfs of the Arabian Sea and the Red sea was observed. In the eastern gulfs, the alternate phases of increasing and decreasing SST anomaly included 1985-1986 to 1989-1990, 1989-1990 to 1994, 1994 to 2000, 2000 to 2004, and 2004 to 2009. In the western gulfs of the Arabian Sea and the Red Sea the phases of warming and cooling included 1985 to 1991, 1991 to 1998-1999, 1998-99 to 2003-2004, and 2003-2004 to 2009. The years with high negative SST anomalies during the FIM were 1986, 1988, 1991, and 1994 in the Gulf of Aden, whereas in the Red Sea, these were 1985, 1988, and 1991. Of these 1985 and 1988 were the La Niña years. The years with strong positive SST anomalies during the FIM were 1986, 1998, 2001, 2004, and 2006 in the Persian Gulf; 1999 and 2006 in Gulf of Oman; 1998 and 2002 in Gulf of Aden; and 1998, 2001, and 2002 in the Red Sea. Of these 1986, 1988, 2002, and 2006 were the El Niño years.
The contrasting features between the eastern and western gulfs of the Arabian Sea could be attributed to their difference in oceanographic features, current systems, and also anthropogenic impact. Being enclosed in semiarid surroundings in the northern edges of the Indian subtropical zone, the western gulfs of the Arabian Sea come under the direct influence of multiple atmospheric pressure systems like the impact of the Siberian high pressure system, the El Niño, Southern Oscillation, the North Atlantic Oscillation, and the IOD [
Sea surface Temperature (SST) is one of the key oceanographic parameters, exerting an influential role in many of the meteorological and oceanographic processes. From 1985 to 2009, the SST of the eastern and western gulfs of the Arabian Sea and the Red sea showed a clear cut signal of warming. The rate of increase of SST was highest in the Persian Gulf followed by the Red Sea. From 1991-1992 onwards, the western gulfs of the Arabian Sea and the Red sea exhibited a sharp increase in SST, whereas in the eastern gulfs of the Arabian Sea, the warming was more pronounced from 1995 onwards. Seasonal differences were also found with respect to increasing temperature. Interannual variability pattern was found to be similar in the annual and seasonal SST amongst the western gulfs and the Red Sea. Similarity in SST variability was also found in the two of the eastern gulfs of the Arabian Sea. Red Sea was found to be warming significantly across all the seasons and months. The largest variation in annual SST was found in the Persian Gulf (CV of 18.02%). The interannual variability in seasonal mean SST was highest in the Persian Gulf in all the seasons except for the SWM season. During SWM season, the maximum variability was observed in the Gulf of Kutch (CV of 10.07%) followed by Gulf of Khambhat (CV of 4.9%). The influence of ENSO and IOD on the SST variability pattern was also found. The impact of rising temperature on other physical and biological parameters of the gulfs of the Arabian Sea and the Red Sea needs to be scrutinized further.
The difference in the oceanographic features of the eastern and western gulfs of the Arabian Sea and the Red Sea, from the open oceans, makes them unique ecosystem. Hence, caution is needed to analyze them individually and not to generalize the findings of the entire basin upon them.
The authors are thankful to NASA’S Jet Propulsion Laboratory’s Physical Oceanographic Centre and Climate Diagnostic Centre for providing the data.