Global Warming and Daylilies

The genus Hemerocallis is also known as the daylily. It is interesting in that the twelve species have varying bloom dates, the day of the first bloom from the first day of the year of the bloom. Thus a bloom data of 130 means 130 days from January 1 of the year of the bloom.

Flowers bloom depending on how the year before was as well as the period just before the bloom. The change in the bloom date for a plant fixed in space over time reflects the conditions of temperature, water, and other factors. It becomes a sentinel for global warming as we shall show.

Now let us first show the temperature, average, and rainfall, total, for our area for the past twenty years.



















We see little global warming but considerable change in total rainfall. Why we really do not know. But rainfall did change considerably.

Now we can show Bloom Date, BD as follows:



















Namely we have Bloom Date dependent on average temperature and total rainfall as an example. From the BD we can determine the global warming factor, namely the change in T the average temperature as a function of time as well as global wetting, the change in W as a function of time. In our case there problem is wetting and not warming.

But before continuing let us look at 20 years worth of data we have collected for the early four species, H minor, flava, dumortierii, middendorfii. They are below:









































































We looked at this raw data, and unlike the Brits we keep data and will share it if requested, and we find a trend of clear shortening of the bloom date. Now that may mean global warming or global wetting or both.

We then use the temperature and rainfall data and then conclude that there was global wetting. That was unquestioned. We frankly were surprised. There was no warming effect observed although at first glance one would have thought so.

Yet this also applies to the tree ring data which follows the same path botanically. One could infer warming when in reality it may be wetting. One thus must be careful to first understand the underlying plant physiology before blindly applying data.