Presentation is loading. Please wait.

Presentation is loading. Please wait.

IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution Lecture 8 Mesoscale variability and coastal pollution.

Similar presentations


Presentation on theme: "IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution Lecture 8 Mesoscale variability and coastal pollution."— Presentation transcript:

1 IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution Lecture 8 Mesoscale variability and coastal pollution

2 This lecture includes the following topics: 1.Phytoplankton, the main contributor to ocean color: -Passive tracer -Active growing biomass 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea 3. Spring bloom in Southern California Bight resulting from coastal upwelling IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes off southern California

3 Multi-discipline approach implies that the simultaneous measurements of distribution of phytoplankton and physical environment enable the studies of physical factors, which determine the distribution of phytoplankton. SeaWiFS surface chlorophyll AVHRR Sea Surface Temperature IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

4 1. Phytoplankton is both a passive tracer transported by water circulation and an active biomass growing under favorable conditions (light, nutrients, etc.). It is important to distinguish between these two processes. Horizontal circulation transports phytoplankton in horizontal direction, resulting in changes in its horizontal distribution. Vertical stratification of water column regulates the growth of phytoplankton biomass. So, the mesoscale variability of phytoplankton visible at satellite images results from both passive transport and active growth. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

5 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The illustrative example of mesoscale variability of phytoplankton is the Black Sea located in southeastern Europe. The abyssal plain of depth more than 2000 m is separated from the margins by steep continental slopes, excluding the shallow northwestern part. The wide northwestern continental shelf (mean depth about 50 m) occupies the region between the Crimean peninsula and the west coast. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

6 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea A basin scale cyclonic boundary Rim Current is the main feature of the Black Sea general circulation. The Rim Current is <75 km wide and has an average speed of 20 cm s -1. Along the coastal lines anticyclonic vorticity arises due to the Rim Current meandering, resulting in anticyclonic eddies in coastal zones. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

7 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea High-resolution AVHRR images enabled studies of the formation and evolution of the cyclonic and near-shore anticyclonic eddies along the coast and their influence on distribution of remote-sensed chlorophyll. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

8 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea These AVHRR images illustrate the dynamics of the cyclonic eddies (C- 1, C-2) and near-shore anticyclonic eddies (NAE-1, NAE-2, etc.) during the autumn 1997. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

9 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea These AVHRR images illustrate the dynamics of the cyclonic eddies (C- 1, C-2) and near-shore anticyclonic eddies (NAE-1, NAE-2, etc.) during the autumn 1997. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

10 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea These AVHRR images illustrate the dynamics of the cyclonic eddies (C- 1, C-2) and near- shore anticyclonic eddies (NAE-1, NAE-2, etc.) during the autumn 1997. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

11 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea These AVHRR images illustrate the dynamics of the cyclonic eddies (C- 1, C-2) and near-shore anticyclonic eddies (NAE-1, NAE-2, etc.) during the autumn 1997. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

12 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The propagation of the near- shore anticyclonic eddies resulted in change of the direction of currents over the continental slope. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

13 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea Hydrographical observations support upwelling in the cyclonic eddies and downwelling in the anticyclonic eddies. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

14 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea Torrential rains in the beginning of October 1997 resulted in increased freshwater discharge and accumulation of phytoplankton and pollutants in the near-shore anticyclonic eddies. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

15 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The concentration of chlorophyll increased in the cyclonic eddies and decreased in the anticyclonic eddies of the open sea. Near-shore anticyclonic eddies accumulated high concentrations of chlorophyll. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

16 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The process of transport of phytoplankton from productive shelf region to the open sea was observed during summer 1998 over the continental slope in the northwestern part of the Black Sea. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

17 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea Anticyclonic eddies slowly moved southwestward along the continental slope. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

18 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The largest anticyclone with diameter of 90 km displaced during three months southwestward with mean speed of about 3 cm/s. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

19 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

20 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

21 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

22 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

23 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

24 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

25 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

26 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

27 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

28 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

29 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

30 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

31 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

32 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

33 2. Horizontal transport of phytoplankton and pollutants offshore in the Black Sea The eddies transported chlorophyll- reach coastal waters to the deep basin. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

34 3. Spring bloom in Southern California Bight resulting from coastal upwelling Circulation in the Southern California Bight is cyclonic, resulting from the interaction between California Current and Southern California Countercurrent. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

35 3. Spring bloom in Southern California Bight resulting from coastal upwelling Strong alongshore wind results in upwelling and phytoplankton bloom. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

36 3. Spring bloom in Southern California Bight resulting from coastal upwelling Strong alongshore wind results in upwelling and phytoplankton bloom. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

37 3. Spring bloom in Southern California Bight resulting from coastal upwelling Strong alongshore wind results in upwelling and phytoplankton bloom. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

38 From Level 3 time-series of SeaWiFS chlorophyll concentration we study statistical correlations between phytoplankton dynamics and environmental factors.

39 Phytoplankton blooms regularly occur in SCB, typically in spring.

40 Seasonal variations of remote sensed SST and chlorophyll biomass averaged over SMB, air temperature at LAX, and wind (upwelling index at 33 o N, 119 o W). Seasonal minima: wind - December 19 (winter solstice); air T - February 7 (+50 days) SST - March 2 (+23 days). Seasonal maximum of Chl (February 27) coincides with SST minimum.

41 Chlorophyll biomass growth results from decrease of air temperature and increase of upwelling-favorable wind stress with time lag 5-6 days.

42 4. Stormwater plumes in southern California Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution

43 Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes in southern California

44 Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes in southern California

45 Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes in southern California

46 Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes in southern California

47 Mesoscale eddies transport offshore the rainstorm plumes with high suspended sediment and chlorophyll concentration. IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution 4. Stormwater plumes in southern California

48 On the basis of SeaWiFS observations collected over 7 years (1997-2004) the basic statistical characteristics of plumes in the Southern California Bight were estimated. Normalized water-leaving radiation of 555 nm (nLw555) wavelength is highly correlated with the concentration of suspended sediments, resulting in brownish water color typical to stormwater plumes. Plume size was assessed from nLw555 exceeding a certain threshold, estimated as 1.3 mW cm -2 µm -1 sr -1. A primary factor regulating the plume size was rainstorm magnitude, i.e., the total volume of water precipitated over the coastal watershed.

49

50

51

52

53 Plume dynamics was studied in four southern California regions: Ventura, Santa Monica Bay, San Pedro, and Orange County/San Diego.

54 Maximum plume size (150-200 km 2 ) was observed from the outlets of the Santa Clara and Ventura rivers, because of higher sediment concentration resulting from highly erosive river beds.

55 In Santa Monica Bay, the optical signature of stormwater plumes was much weaker (0.8 mW cm -2 µm -1 sr -1 ) than in other regions (1.3 mW cm -2 µm -1 sr -1 ).

56 In San Pedro region, typical plume size was 10-80 km 2. The time lag between rainstorm and maximum plume size in this area was 1 day, in contrast to 2 days in three other regions.

57 In Orange County/San Diego region, typical plume size was small (10-40 km 2 ), resulting from bimodal watershed physiography, where river flow is often retained in the inland alluvial valleys.

58 In San Pedro region, the correlation between the precipitated rainwater and the plume size was almost linear, resulting from highly impervious surface in these developed watersheds.

59 In three other regions, power function better described the correlation between rainwater and plume size, resulting from more natural watersheds where water is partly infiltrated.

60

61

62 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

63 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

64 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

65 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

66 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

67 The direction of plume propagation results from the near-shore circulation. In particular, during spring transition typical to California Current System, equatorward currents associated with wind-driven upwelling can transport stormwater plumes downcoast.

68 IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution


Download ppt "IoE 184 - The Basics of Satellite Oceanography. 8. Mesoscale variability and coastal pollution Lecture 8 Mesoscale variability and coastal pollution."

Similar presentations


Ads by Google