There is a flower population elevated 1000 meters above sea level. If climate change causes a 12 degree C increase in temperature over the next 10 years, what will happen to the flowers?
Its really hard to say for any given field of flowers and its hard to separate temperature from so many other factors that are accompanying climate change.
For example, rainfall is changing as well as CO2 levels. The pH of the rain may change because CO2 becomes a mild acid when its absorbed into water. The speed at which the seasonal temperatures vary and how cold is the minimum temperature and how hot is the hottest day will cause parasites and infections which kill plants to appear.
To be sure the heat is important, but the timing maybe just as important. The temperature is causing earlier blooms and later growing seasons.
Each different species is responding differently, but odds are that nearly any given field of flowers is going to feel it. The temperature is important, but its sometimes hard to guess if its the specific culprit in changes.
Making one change in an ecological system is much like eating one salted peanut.
A: If you assume only a 12 degree change (which is really large) then the net effect is not only warmer but dryer. Higher temperatures mean faster evaporation, faster transpiration.
B: Warmer may also mean taht some pest has a limiting factor removed. Look at the problem northern British Columbia has had with Mountain Pine Beatle. The pines are fine with the warmer winters. But the lack of cold winters has allowed the beatle population to explode.
C: Some plants are adapted to a large temerature range. Look at the range for dandelion. So warmer temps may make them grow faster and set seed sooner.
D: Some plants are adapted to a narrow temp range, and will die out.
One of the questions is, "If the change is slow enough, won't they just move up the mountain. In some cases yes. We can look at turn of the century (1900) photographs of mountains, and we can see the tree line -- both at the top, where it meets tundra, and at the bottom where it meets prairie -- has moved up the mountain.
However it also depends on the soil. And soils neither move fast, nor are created fast.
Example: Lot of articles think Canada will win big with global warming, because more northerly land will be suitable for farming. Not so. Most of the land that has reasonable soil is already farmed. The soil north of that point tends to be mostly peat moss bogs, and glacial till. In addition over half that country is the Precambrian shield -- endless miles of granite under 2-3 inches of moss and gravel, with bogs and lakes between. The equivalent of a rural gravel road costs millions of dollars a mile to punch through this country.