As part of the government funded science challenges, Water
New Zealand has been invited to participate in “Deep South Science Challenge”
dialogue on drought. The outcomes of the dialogue will be funded research
projects that look at the Impacts and Implications of climate projections of
drought.
Impacts and Implications
projects will build on improved understanding of future climate and existing
initiatives developed by NIWA;
Scientists noted that
projections of soil moisture and drought remain relatively uncertain compared
to other aspects of the water cycle. Nonetheless, a major message is that
drought severity increases over time, and the extent will be influenced by the
extent of future greenhouse gas emissions. Key takeaways from NIWA were:
- Drought risk is expected to increase this
century in already drought-prone areas,
- ‘Severe droughts’ occur more often by mid and
late-century and worsen as greenhouse gas forcing increases
- Low flow conditions are expected to be
reached earlier in the water year for much of the North Island and eastern
South Island, increasingly so with higher radiative forcing scenarios and
towards the end of the century (except the West Coast)
- Summer Mean conditions during spring, summer
and autumn seasons are expected to remain about the same or become slightly
wetter by mid-century for the lowest radiative forcing scenario. With
increased radiative forcing and time, soil moisture conditions are expected to
become drier in the North Island and in South Canterbury, Otago and Southland.
- Soil Moisture Deficit conditions during
summer are expected to remain about the same or become slightly lower by
mid-century. With increased radiative forcing and time, soil moisture
deficit conditions are expected to increase in the North Island while reducing
in South Canterbury, Otago and Southland.
- Less stream water will be available during
summer months, and that there is likely a potential reduction of
agricultural/plant water needs in the summer months in South Island versus an
increase in the North Island.
The projects will complement existing water related research
projects being undertake as part of the challenge;
Members with an interest in
existing research streams, or feedback on research priorities for the upcoming
funding round should contact: Lesley.smith@waternz.org.nz.
Priorities for future research will be developed at a workshop on 12th June.