With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct ? 1. OMT is measured up to a depth of 26℃ isotherm which is 129 meters in the south-western Indian Ocean during January - March. 2. OMT collected during January - March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean. Select the correct answer using the code given below :

Explains the vertical temperature structure and names the thermocline as the boundary where temperature falls rapidly from surface to depth.

A student could check whether the 26°C isotherm commonly lies within or near the thermocline (100–400 m) in various regions to judge use of that isotherm as an OMT bottom.

Repeats the thermocline definition and the typical depth range (about 100–400 m) and notes deep-ocean temperatures approach 0°C.

Compare the typical depth of the 26°C isotherm (using sea temperature profiles or maps) with the thermocline depth given here to assess if 26°C is a consistent OMT marker.

Gives an example using a specific temperature threshold (~27°C) and a warm-water layer depth (60–70 m) important for tropical storms, showing thresholds and depth-layers are used in ocean studies.

Use this example of a temperature threshold and associated depth to infer that other specific isotherms (e.g., 26°C) can be used as practical layer boundaries for measurements like OMT, especially in the tropics.

Provides typical surface temperature values (about 27°C at the equator) and notes latitudinal decline, indicating where a 26°C isotherm might be located geographically.

Combine these surface temperatures with a world map to locate regions where a 26°C surface or subsurface isotherm is plausible, helping to test whether measuring down to that isotherm would capture a meaningful warm layer.

Describes rates of temperature decrease with depth (rapid near surface, slower below), giving a basis for understanding how deep a particular isotherm (e.g., 26°C) might occur.

Apply the described vertical temperature gradients to estimate approximate depths of given isotherms in different regions to evaluate the practicality of using the 26°C isotherm as an OMT boundary.

Gives the general vertical temperature structure and locates the thermocline boundary usually around 100–400 m where temperature drops rapidly.

A student could infer that a 26°C isotherm in the tropics/low latitudes likely lies within this thermocline band and thus check whether ~129 m is plausible for SW Indian Ocean January–March.

States typical surface monthly temperatures: equatorial oceans >24°C and mean January temperatures over 27°C in some regions, indicating surface waters in the tropics commonly exceed 26°C in winter months.

Combine surface temperature norms with the thermocline depth (snippet 9) to estimate where the 26°C contour would descend offshore in January–March.

Explains that western Indian Ocean can warm (e.g., during El Niño) because heat is retained; implies relatively deep warm-surface layers compared with other oceans.

Use the idea of retained heat in the western Indian Ocean to expect a deeper 26°C isotherm there than in cooler regions, making 129 m more plausible.

Notes observed warming in the South Indian Ocean (surface temps rising from ~26.5°C to 30–32°C), indicating the 26°C surface contour may shift in space/depth with recent warming.

A student could use reported surface warming to reason that the 26°C isotherm may sit deeper or be displaced seasonally, so verifying a specific 129 m depth requires contemporaneous profiles.

Describes major warm currents (Agulhas/Mozambique) that transport warm water poleward in the southern Indian Ocean, affecting vertical and horizontal temperature distribution.

Map the position of these currents relative to the SW Indian Ocean and anticipate deeper warm-water penetration (and thus deeper 26°C isotherm) where warm currents persist in Jan–Mar.

States monsoon understanding uses data collected on oceans and upper atmosphere and that IMD forecasts monsoon behaviour using multiple indicators.

A student could infer OMT is the kind of ocean variable IMD might include among indicators and test correlation with monsoon rainfall.

Explains monsoon mechanism depends on land heating/cooling relative to ocean, linking ocean state to monsoon winds and rainfall.

Combine this with Jan–Mar OMT anomalies (warm/cool) to hypothesize effects on land–sea temperature contrast and subsequent monsoon strength.

Notes thermal concepts of monsoon and complexity (convectional, orographic, cyclonic), implying ocean-driven thermal patterns can influence monsoon but aren't sole cause.

Use this to caution that OMT may be one contributing predictor and should be tested alongside other factors.

Describes March–May as the hot season when the heat belt shifts north, identifying March as start of the pre-monsoon warming period.

A student could compare Jan–Mar OMT with concurrent land heating patterns (from maps/temperature data) to assess potential impacts on subsequent monsoon onset/intensity.

Points out January is coldest month in India and coastal moderation by oceans, implying ocean temperatures in Jan–Mar can affect coastal/regional thermal contrasts relevant to monsoon dynamics.

Extend by checking whether anomalous coastal OMTs in Jan–Mar reduce or enhance land–sea contrast that influences monsoon circulation.