## Contour Lines ( Isolines ) and Imaginary line in the map

**What is Contour Lines (Isolines) ?**

Isolines, also referred to as contour lines. The prefix ‘iso’ is a greek word meaning equal, so an isoline must be a line joining equal points.

A contour line or Isolines are imaginary lines that connect points of equal elevation (elevation refers to height in feet, or meters, above sea level). Contour lines, isolines,* o*r isograms are used widely in different fields such as meteorology, geology, oceanography, and other sciences to represent lines with equal values of a certain attribute.

**The following are general characteristics of contour lines:**

- Contour lines do not cross each other, divide or split.
- Closely spaced contour lines represent steep slopes, conversely, contour lines that are spaced far apart represent gentle slopes.
- Contour lines trend up valleys and form a “V” or a “U” where they cross a stream.

Here’s a list of Contour Lines / types of Imaginary line in the map you might discover as you explore geography .

### List of Contour Lines ( Isolines ) /Imaginary line in the map

S.N. |
Name of Contour Lines (Isolines) |
Definition |

1 | Isabnormal | A Line connecting points of equal deviation from mean temperature |

2 | Isacoustic | A Line connecting points of equal acoustic quality |

3 | Isallobar | A Line connecting points of equal change in barometric pressure |

4 | Iseidomal | A Line connecting points of equal visibility of a spectacle |

5 | Isentropic | A Line connecting points of equal entropy |

6 | Isobar | A Line connecting points of same atmospheric pressure |

7 | Isobase | A Line connecting points of equal land upheaval |

8 | Isobath | A Line connecting points of equal underwater depth |

9 | Isobathytherm | A Line connecting points of equal temperature and depth underground |

10 | Isobront | A Line connecting points of simultaneous storm development |

11 | Isochar | A Line connecting points of similar distinguishing characteristics of plant life |

12 | Isochasm | A Line connecting points of equal frequency of aurorae |

13 | Isocheim | A Line connecting points of same average winter temperature |

14 | Isochlor | A Line connecting points of equal chlorine concentration |

15 | Isochor | A Line connecting points of varying conditions under constant volume |

16 | Isochrone | A Line connecting points of equal time difference or simultaneous occurrence |

17 | Isoclinal | A Line connecting points of same magnetic dip |

18 | Isocryme | A Line connecting points of equal winter temperature |

19 | Isodapane | A Line connecting points of equal transport costs for products from production to markets. |

20 | Isodose | A Line connecting points that receive equal doses of radiation |

21 | Isodrosotherm | A Line connecting points of equal dew point |

22 | Isodynamic | A Line connecting points of equal magnetic intensity |

23 | Isoflor | a Line connecting points of equal number of plant species |

24 | Isogam | A Line connecting points of equal acceleration due to gravity |

25 | Isogen | A Line connecting points of equal birthrates |

26 | Isogeotherm | A Line connecting points of equal subterranean temperature |

27 | Isogloss | A Line connecting points of similar regional dialect |

28 | Isogon | A Line connecting points of same specified angle or same wind direction |

29 | Isogonal | A Line connecting points of equal magnetic declination |

30 | Isograd | A Line connecting points of similar conditions during geological metamorphism |

31 | Isogram | A Line connecting points on a map having some similar feature |

32 | Isograph | A Line connecting points of same linguistic usage in some respect |

33 | Isohaline | A Line connecting points of equal salinity |

34 | Isohel | A Line connecting points of equal sunlight |

35 | Isohyet | A Line connecting points of equal rainfall |

36 | Isokeraunic | A Line connecting points of equal occurrence of thunderstorms |

37 | Isolex | A Line connecting points of same vocabulary usage |

38 | Isoline | A Line connecting points on a map having some similar feature |

39 | Isomagnetic | A Line connecting points of equal magnetic induction |

40 | Isometric | A Line connecting points of equal variations of pressure |

41 | Isomorph | A Line connecting points of same linguistic morphological forms |

42 | A sonephelic | A Line connecting points of equal cloud cover |

43 | Isopach | A Line connecting points of equal thickness of geological strata |

44 | Isophene | A Line connecting points of the same phenotype or seasonal variation |

45 | Isophote | A Line connecting points of equal light intensity from a given source |

46 | Isopiestic | A Line connecting points of equal pressure but varying temperature and volume |

47 | Isopiptesis | A Line connecting points of same arrival date of migratory species |

48 | Isopleth | A Line connecting points of equal aspect of climate |

49 | Isopor | A Line connecting points of equal annual change in magnetic field |

50 | Isopycnic | A Line connecting points of equal density |

51 | Isorithm | A Line connecting points of equal population density |

52 | Isoseismal | A Line connecting points of same earthquake intensity |

53 | Isostere | A Line connecting points of equal specific volume of a substance |

54 | Isotac | A Line joining points where the ice melts at the same time of year |

55 | Isotach | A Line connecting points of the same wind speed |

56 | Isothere | A Line connecting points of equal summer temperature |

57 | Isotherm | A Line connecting points of equal temperature |

58 | Isothermobath | A Line connecting points of equal temperature at a given ocean depth |

59 | Isotherombrose | A Line connecting points of equal ratio of summer rainfall to annual rainfall |

60 | Isovol | A Line connecting points of equal ratio of fixed to volatile carbon in coal |