Download possible impacts of climate change on lakes and wetlands in hungary

4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
POSSIBLE IMPACTS OF CLIMATE
CHANGE ON LAKES AND
WETLANDS IN HUNGARY
Sándor Szegedi*- Zoltán Karácsonyi** Károly Tar*-and Andrea Kircsi*
*Department of Meteorology,University Of
Debrecen
**Centre for Environmental Management and Policy
University Of Debrecen
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Introduction – changes in the
hydrological conditions in the Carpathian
Basin during the last 150 years
• Since
the
1850’s
landscape
and
hydrology of the Carpathian Basin has
altered
significantly
due
to
regularization of riverways and lakes.
• Before the regularization works there
were waste areas of wetlands in the
low-laying regions of the Carpathian
Basin.
• Permanently and periodically (2-6
months in a year) flooded areas
occupied more than a quarter of the
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• During the regularization works (from
1846) river meanders were cut off,
periodically flooded areas and swamps
along rivers and lakes were drained.
• Only along the River Tisza 111 meanders
were cut off.
• Dams were built in order to prevent floods
and to gain agricultural land.
• More than 6,400km of dams and nearly
12,000km of canals were built.
• Consequently, the extent of wetlands
decreased remarkably (from 25,000km2 to
1,200km2 from total 93,000km2 area of the
country).
• Wetlands have survived only between dams
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Climate change in Hungary – Today…
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• Trends of climate elements show
considerable changes within the time
span of meteorological observations.
• Since
the
establishment
of
the
meteorological observation network
(1870) in Hungary there has been an
increase
of
the
annual
mean
temperatures of 1°C, while the amount
of annual mean precipitation has
decreased by 100mm in the West and
50mm in the East.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Trends
of
precipitation
in
some
weather
stations
representative for the Great Hungarian Plain and the
watershed of Lake Balaton during the 1955-2000 period
compared to the annual mean of the 1961-1990 period.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
…and Tomorrow
• The main problem is that little is known
about the regional effects of climate
change, since global scenarios for
climate change and Global Circulation
Models have a resolution of several
hundreds of kilometers.
• For this reason, downscaling of global
scenarios or GCM outputs is necessary
for regional forecasting.
• Climatological variables at a given
time and location are strongly
influenced by atmospheric circulation
patterns,
therefore
climatic
variability may be related to changes
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• Former studies have found strong
relationships
between
daily
and
monthly changes of water budget
elements (surface inflow, precipitation,
evaporation)
and
large
scale
circulation patterns (CP).
• Outputs of T21 GCM of Max Planck
Institute of Hamburg for 1×CO2 and 2×CO2
concentrations have been used for the
simulations.
• Using a semiempirical downscaling
approach, changes of atmospheric
circulation patterns, their occurrence,
persistence and transition probabilities
have been analyzed and linked to
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Climate change: Lake Balaton and the
Great Hungarian Plain
• The largest lake of Hungary and
Central Europe is Lake Balaton. Its
area is 600km2.
• It is a shallow lake similarly to all
other lakes in Hungary. Its average
depth is only 3m (11m is its maximal
depth), what makes it extremely
sensitive to climate variability.
• Since Roman times there had been severe
fluctuations in the water level of the
lake. During the last decades of 20th
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Lake Balaton water supply
- Extremely low water level (reason:
2000-2003
low precipitation in the watershed)
- Water supply – necessary?
- Source: riverine (Danube, Mura, Rába,
Dráva)
or karst-water?
- strong civil interest (for and
against)
- high touristic importance
- strong local support (economic
reasons)
Strategic environmental assessment
Outcome: the plan is given up primarily
for ecological reasons.
Municipality Board meeting on a dune
(August, 2002.)
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• One of the most serious challenges of
20th/21st century from the aspect of
hydrology is climate change.
• Processes linked to alterations of
climate may have strong impacts on
surface waters.
• For this reason examinations have been
carried out to trace and model those
impacts on the elements of the water
budget in the watershed of Lake
Balaton and the Great Hungarian Plain,
which are the most sensitive regions of
Hungary from the aspect of climate
change.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• Model results show that there will
be relatively strong changes in the
water budget elements in the case of
2× CO2 scenario.
• Evaporation will increase by 3-4% in
the summer season.
• The amount of precipitation on rainy
days will increase but the number of
rainy days will decrease.
• On the other hand in the winter
season the Southern part of the
watershed will be a bit wetter, while
the rest of the region will be dryer.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Anomalies of the amount of precipitation on rainy
days for the watershed of Lake Balaton simulated
by a stochastic embedded model for 2×CO2 climate
(Bartholy, 2004).
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• The amount of precipitation of rainy
days will decrease as well.
• No significant changes are detected in
the probability distribution of dry
period duration.
• As a consequence of changes in
evaporation and precipitation inflow
and uncontrolled volumetric change
may be altered strongly.
• As a result lakes and wetlands may
become even more sensitive to changes
of climate elements in the future.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Complex Habitat Rehabilitation of the Central
Bereg Plain, Northeast Hungary
• Since 1990 projects has been launched for
revitalization of wetlands in the Danube
and Tisza valley (in the Great Hungarian
Plain) as well.
• Our department is involved in a project
carried out by the Hortobágy National
Park.
• The endangered wetlands of the Central
Bereg Plain are located in the least
developed region of Hungary next to the
border with Ukraine.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• Raised bogs evolved under very specific
microclimatic conditions in the Great
Hungarian Plain, and represent the
southernmost relict of this type of
ecosystem in Central Europe.
• The LIFE project area has suffered long
term degradation by human activities.
• The main causes are desiccation by
agricultural
drainage
during
the
socialist era, increasing eutrophication
by agricultural chemicals, erosion from
surrounding arable areas and a lack of
renewal of the wood stock in cultivated
forests.
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
• By the end of the project, the restored
hydrology of the area should provide
the ideal microclimatic conditions to
help these wetlands recover in the dry
pannonic climate.
• At the same time, scientific monitoring
will lay the basis for the long-term
maintenance of the rehabilitated
areas.
• As a part of the monitoring the aim of
our measurements is to detect the
special microclimate features of the
4. LAKEPROMO SEMINAR 17.05 – 18.05.2006
Pühajärve, ESTONIA
University of Debrecen, HUNGARY
Centre for Environmental
Management and Policy
Thank you for your
attention!