What makes climate, and the world's biomes

Grade 9 Social Studies Worksheet - Building Confidence

Circle the best answer.

1. Read this first

   Four cities and the sunlight at their latitudes

   City	Latitude (about)	January normal (°F)	July normal (°F)
   Miami	26°N	69	84
   New York	41°N	34	78
   Anchorage	61°N	17	60
   Utqiagvik, Alaska	71°N	-12	42

   Note: NOAA 1991-2020 normals are averages over 30 years. Weather is the conditions on one day. NASA: at an equinox, sunlight reaching the ground is about 90% of the equator's in the tropics, about 70% at 45° and about 40% at the polar circles (66.5°).

2. 1.

   July minus January is 15°F in Miami, 44°F in New York, 43°F in Anchorage and 54°F in Utqiagvik. Bo says the swing grows steadily with latitude. Is that right?

   • Not quite: it grows to Utqiagvik, but New York's 44°F is a degree more than Anchorage's 43°F
   • Yes: each city farther north has a bigger swing than the city before it, so it grows steadily north
   • No: Miami has the biggest swing, because it has the warmest July of the four cities
   • No: the swing is smallest at Utqiagvik, where sunlight is least in the four cities
3. 2.

   Sunlight falls from about 90% in the tropics to about 70% at 45°. New York's January is 35°F colder than Miami's. What can Esme say about the two facts?

   • Each point of sunlight lost cools January by 1.75°F in each city, since 35 divided by 20 is exactly 1.75
   • Sunlight cannot affect January, since the sun is weakest in winter at each latitude, so another cause is at work
   • Less sunlight fits the colder January, but no card gives a rule turning sunlight points into degrees
   • The January gap equals the 35 degrees of latitude between the two cities
4. 3.

   One July day in Anchorage reaches 72°F. Jun says Anchorage's July climate is therefore 72°F, not the 60°F normal. What is the reply?

   • The 60°F normal must be wrong, since one day hotter than the normal shows it is too low
   • A normal is a 30-year average, so one hot day is weather and does not change the 60°F normal
   • Weather and climate are the same thing, since both are measured in degrees
   • Climate is the most common temperature, so 72°F becomes the climate if it happens again
5. 4.

   Anchorage's January normal is 17°F and its July normal is 60°F. Miami's are 69°F and 84°F. Which statement does Kira support?

   • Miami's swing is larger than Anchorage's, because Miami has the warmest July
   • Anchorage's swing is 43°F more than Miami's, so it is about 58°F
   • Anchorage's swing, 43°F, is nearly three times Miami's swing of 15°F
   • Anchorage's swing is about twice Miami's, since its July is 24°F colder than Miami's
6. 5.

   Utqiagvik's January normal is -12°F. Luz says no January day there is ever warmer than 0°F. What is wrong with that?

   • A normal is an average, so some January days can be warmer than it and some colder
   • A 30-year average cannot be used for single days, so Utqiagvik has no January climate
   • Nothing, since a normal sets the highest temperature that can occur on any January day
   • The normal means each January day is colder than -12°F, since it is a long-term low
7. 6.

   Utqiagvik's January normal is -12°F and Miami's is 69°F. Milo says the polar circles get 40% of the tropics' sunlight, so -12°F is 40% of 69°F. Is that sound?

   • Yes: sunlight at the polar circles is 40%, so temperature there must be 40% as well
   • No: Utqiagvik is at 71°N, beyond the polar circles, so just Miami's value is a share
   • No: -12°F is below zero, so it cannot be 40% of 69°F; temperature does not scale with sunlight
   • Yes: 40% of 69°F is about 28°F, which is near -12°F once the winter effect is added
8. 7.

   Anchorage lies at about 61°N, between 45° (about 70%) and the polar circle at 66.5° (about 40%). How much of the equator's sunlight does Noah expect?

   • Exactly 55%, the middle of 40% and 70%, since 61° is the middle of the bands
   • About 90%, since Anchorage is in the Northern Hemisphere with the tropics
   • Between about 40% and 70%, since 61° lies between the two bands
   • Under 40%, since Anchorage is past the polar circle
9. 8.

   Miami's January normal, 69°F, is warmer than Anchorage's July normal, 60°F. What does Ren learn from that?

   • Anchorage must be cold because it is 61°N, so its July cannot be 60°F
   • Season matters more than latitude everywhere, so winter in Miami beats summer in Anchorage
   • Miami is warmer in January just because its July is warmer, so July sets January
   • A place at 26°N in its coldest month can be warmer than one at 61°N in its warmest
10. 9.

    The sunlight shares are for an equinox. Tala lines them up with each city's July and January normals. What is a fair view?

    • They are useless for temperature, since they describe a single moment
    • They show which latitudes are sunnier on average, but they do not give each month's temperature
    • They give each month's temperature, since the equinox is a typical day for each month
    • They tell the January temperature, but not the July one, since the equinox is in spring
11. 10.

    NOAA normals average 30 years, while NASA's sunlight shares describe one moment. Zee sets them side by side. What should Zee keep in mind?

    • A 30-year average is more accurate than a single moment, so the normals replace the shares for any city
    • They fit together as a general pattern, but they measure different things over different spans
    • The shares explain the whole of each normal, so no other factor needs to be considered
    • They measure the same thing, so differences between them show errors in one of them