Group 1

Mobile, Alabama

Alana SmithMeredith Karr

Charles EdwardsChris SwaimLindsay Ash

Station ID: Mobile Regional AirportLatitude: 30° 41’ 29”Longitude: 88° 14’ 34”Elevation: 219 feet

Average Temperature 1950-2008

1950

1953

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

2007

62

63

64

65

66

67

68

69

70

f(x) = − 0.00101694915254238 x + 67.3949152542373R² = 0.00036533131771066

Year

Mea

n Te

mp

Average Temperature 1988-2008

1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 200865

65.5

66

66.5

67

67.5

68

68.5

69

f(x) = 0.0287012987012987 x + 67.0604761904762R² = 0.0635691167665943

Average Temperature Jan/Jul

19501953

19561959

19621965

19681971

19741977

19801983

19861989

19921995

19982001

20042007

3540455055606570

f(x) = − 0.0228579777907656 x + 51.550146113384R² = 0.00663533482052425

January Ave Temps

Year(

s) 1951

19531955

19571959

19611963

19651967

19691971

19731975

19771979

19811983

19851987

19891991

19931995

19971999

20012003

20052007

75

80

85

90

f(x) = 0.00422559906487435 x + 81.8308591466979R² = 0.00342025189768469

July Ave Temps

Jul

Linear ( Jul )

•Summer based on July temperatures

•Winter based on January temperatures

•Average mean temperatures changed little over the 58 years

•Summer temperatures stayed between 79° F and 84.6° F

•Winter temperatures stayed between 40.9° F and 64.6° F

•Variation occurred from one year to the next, but the trend lines show very little change occurred on average

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 200530

35

40

45

50

55

60

65

70

75

80

85

90

f(x) = 0.00422559906487435 x + 73.5951665692577R² = 0.00342025189768635

f(x) = − 0.0228579777907656 x + 96.1003448275861R² = 0.00663533482052403

Average Mean Summer and Winter Temperatures in Mobile

Average Mean Winter Temerpature in MobileLinear (Average Mean Winter Temerpature in Mobile)

Year

Tem

pera

ture

in D

egre

es F

ahre

nhei

t

Why might the average mean summer and winter temperatures in Mobile stay relatively

constant?•Mobile is adjacent to the Gulf of Mexico

•Oceans warm and cool more slowly than land • Because water temperature does not change as quickly as air

temperature, the temperature of nearby areas remain more constant

•Most landforms heat up relatively quickly during the day and cool down relatively quickly at night, which affects air temperature through the radiant heating and radiant cooling process.

• Yet, the ocean temperature counteracts these processes by not changing temperatures as quickly.

•Thus, large bodies of water moderate long-term temperature averages.

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 200530

35

40

45

50

55

60

65

70

75

80

85

90

f(x) = 0.00780245470485097 x + 64.3826709526592R² = 0.00841333330815719

f(x) = − 0.0198889538281707 x + 84.1365108123904R² = 0.00516749324599475

f(x) = 0.00422559906487435 x + 73.5951665692577R² = 0.00342025189768635

f(x) = − 0.0228579777907656 x + 96.1003448275861R² = 0.00663533482052403

Average Mean Temperature Comparison in Mobile and Alabama for Winter and Summer

Average Mean Winter Temperature in MobileLinear (Average Mean Winter Temperature in Mobile)Linear (Average Mean Winter Temperature in Mobile)

Year

Tem

pera

ture

in D

egre

es F

ahre

nhei

t

•On average, the summer temperatures in Mobile are slightly higher than the summer temperatures in Alabama as a whole

•On average, the winter temperatures in Mobile are slightly higher than the winter temperatures in Alabama as a whole

•Average mean summer and winter temperatures tend to be warmer in the southern parts of the state and cooler in the northern parts of the state

•Factors that may contribute to this: • Continentality• Latitude• Altitude

Why might Mobile’s average mean summer and winter temperatures be

slightly higher than the rest of the state?

Continentality•The ocean has a big influence on land areas near it (such as Mobile)

•So, if surrounded by land, the ocean doesn’t have as much influence (as is the case with most of Alabama)

•Thus, Alabama’s humid subtropical climate becomes more temperate with distance from the coast

Latitude•Low latitudes (near the Equator, or 0º Latitude) see the most direct sunlight.

• Usually warmer• Mobile has one

of the lowest latitudes in the state

•High latitudes (near the poles, or 90º North or South Latitude), see the least amount of direct sunlight.

• Usually colder

Altitude•Normally the the higher the elevation, the colder the temperature.

•Map shows that Mobile is one of the cities with the lowest elevation, making it warmer than many other places in Alabama

•Although the average mean summer and winter temperatures vary from year to year, there is very little overall change during the 58 years observed because the Gulf of Mexico moderates the city’s long-term temperature averages.

•Summer and winter average mean temperatures tend to be warmer in Mobile than Alabama as a whole because of its close proximity to the Gulf of Mexico, lower latitude and lower elevation.

Conclusions about Mobile’s Average Mean Summer and Winter Temperatures

Days over 90oF and 85oF

•Projected 3-7 degree rise in summer highs

•Temperature as part of heat index

Days over 90oF

Annual Days over 90 deg rees

y = -0.122x + 316.23R 2 = 0.01570

20

40

60

80

100

120

1940 1950 1960 1970 1980 1990 2000 2010 2020

Days Over 90

L inear (Days Over90)

Summer Days over 90oF

S ummer Days over 90 deg rees

y = -0.0537x + 165.08R 2 = 0.0068

30

40

50

60

70

80

90

1940 1950 1960 1970 1980 1990 2000 2010 2020

S ummer daysover 90Trend

Past 20 Years

Days over 90 deg rees1988-2008

y = 0.3338x - 594.2R 2 = 0.01990

20406080

100120

1985 1990 1995 2000 2005 2010

P as t 20 Y ears

L inear (P as t 20Y ears )

Days over 85oF

Days over 85 deg rees

y = 0.0172x + 101.67R 2 = 0.0011110

120

130

140

150

160

1940 1950 1960 1970 1980 1990 2000 2010 2020

Days over 85

Trend

Summer Days over 85oF

S ummer Days over 85 deg rees

y = 0.0085x + 67.963R 2 = 0.001270

75

80

85

90

95

1940 1960 1980 2000 2020

S ummer days over85Trend

Past 20 Years

Days over 85 deg rees1988-2008

y = 0.9134x - 1688.8R 2 = 0.5637120

125130135140145150

1985 1990 1995 2000 2005 2010

P as t 20s moothed

Trend

Conclusions

• Overall Slight cooling

• Summer matches overall trend

• Increase in past 20 years

• Urban Heat Island?

Precipitation

Annual Precipitation

1940 1950 1960 1970 1980 1990 2000 2010 20200.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

Annual Precipition- Mobile, Alabama

Annual Linear ( Annual )

Difference of Precipitation from Year to Year

50-5152-53

54-5556-57

58-5960-61

62-6364-65

66-6768-69

70-7172-73

74-7576-77

78-7980-81

82-8384-85

86-8788-89

90-9192-93

94-9596-97

98-9900-01

2002-03

2004-05

2006-070

5

10

15

20

25

30

35

40

Series1

Years with a 10+ Fluctuation1950-59 1960-69 1970-79 1980-89 1990-99 2000-08

5.68 24.2 14.76 21 25.7 8.91

2.1 31.95 5.41 17.32 11.21 17.83

2.34 2.05 21.06 9.02 10.06 1.55

24.6 11.02 9.27 29.64 5.48 5.23

31.39 6.37 25.03 16.15 25.57 2.33

.03 5.13 28.08 10.63 13.76 24.48

1.09 8.99 6.07 7.78 13.41 5.9

2.79 17.38 4.22 4.87 6.38 13.85

3.44 19.02 10.46 1.75 35.62

14.8 6.95 1.13 8.03 5.16

3 5 5 5 7 3

Frost

There are certain temperatures which, in one sense or another are recognized as being critical. One of these is the freezing point of water, or 32°F.

The frost season is determined by the first and last dates of the year on which the minimum temperature stinks below 32°F.

19501953

19561959

19621965

19681971

19741977

19801983

19861989

19921995

19982001

20042007

24-Oct

3-Nov

13-Nov

23-Nov

3-Dec

13-Dec

23-Dec

2-Jan

12-Jan

f(x) = 0.119988310929281 x + 40138.8410286382R² = 0.0162014742894977

First Frost of the Year

Series1

Linear (Series1)

Year

Date

In Mobile, the first frost of the year shows the trend of coming about 6 days later than it did in 1950, with the exception of the last 3 years.

In Mobile, the last frost of the year also shows the trend of getting later in the last 68 years. According to the slope, the last frost of the year occurs about 5 days later than it used to.

1940 1950 1960 1970 1980 1990 2000 2010 202028-Nov

18-Dec

7-Jan

27-Jan

16-Feb

8-Mar

28-Mar

17-Apr

f(x) = 0.0887784921098773 x + 39696.8666861485R² = 0.00841760075134956

Last Frost of the Year

Series1Linear (Series1)

Year

Date

Why Frost matters?... Because it determines the length of the growing season. Mobile has one of the longest growing seasons in the United States.

150

170

190

210

230

250

270

290

310

330

350f(x) = 0.0624189784806844 x + 267.049498746867R² = 0.00177121412601067

Length of the Growing Season

Series1Linear (Series1)

Year

Num

ber o

f Day

s with

out F

rost